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Posted 7/11/10 DNA nabs three serial killers in four years, most recently through a familial search
By Julius (Jay) Wachtel. From all the hoopla surrounding the arrest of the “Grim Sleeper” (so dubbed because after an unexplained hiatus he supposedly rose to kill again) one would think it marks the end of a decades-long quest to capture the city’s most murderous evildoer. Well, think again. Thanks to DNA, LAPD detectives have arrested three – that’s right, three – serial killers in the last four years, and Lonnie Franklin isn’t necessarily the most prolific. 
April 30, 2007 was the day that society finally washed its hands of Chester Turner. Convicted of raping and strangling ten women and causing the death of a viable fetus, the middle-aged crack dealer had passed the final two decades of the twentieth century preying on prostitutes in the poverty-stricken neighborhoods that image-conscious politicians recently christened South Los Angeles but locals still call south-central. In 2002 Turner’s imprisonment on a rape conviction led authorities to place his DNA profile in the state databank. One year later an LAPD cold-case detective matched DNA from a 1998 south-central murder to Turner. Assembling profiles from dozens of similar killings, the detective matched Turner to nine more. But there was a glitch. You see, three had already been “solved” with the 1995 conviction of another Los Angeles man, David Allen Jones. A mentally retarded janitor in jail for raping a prostitute, Jones initially denied killing anyone. Detectives finally badgered him into making incriminating statements in three cases. Only problem was, as the D.A. later conceded, his blood type didn’t match biological evidence recovered from his alleged victims. But prostitutes have complicated sex lives, so prosecutors convinced the jury that this apparent inconsistency wasn’t definitive. Jones was exonerated and freed in March 2004. He was compensated $800,000 for his eleven years in prison. Well, Turner’s DNA was present. At trial his attorney argued that it only proved that his client had sex with the women, not that he killed them. Jurors were unswayed. Turner is presently on death row awaiting execution. 
During the mid-1970’s someone was raping and killing elderly white women in southwest Los Angeles county. After subsiding for a few years the murders resumed nearly forty miles to the east, in the Claremont area. By 2009 there were two dozen, all unsolved. Meanwhile, back in south-central, detectives were still on the trail of one or more killers, as many more prostitutes were slain than could be attributed to Turner. Finally in 2002 Chief Bratton ordered his troops to form a cold-case squad. Detectives began comparing biological evidence from unsolved cases in south-central to the DNA profiles of sex-crime registrants. One of these was John Thomas, 72, a parolee who had been imprisoned for rape in 1978. Although his DNA didn’t match any of the south-central killings, it matched at least two of the southwest homicides. His time in prison also coincided with the interval between the waves of murder, and he was paroled to Chino, not far from Claremont. Thomas was arrested in April 2009. After more DNA testing he faces trial in seven killings. Detectives think that he is responsible for others as well. By 2008 the south-central investigation was stalled. All remaining crime-scene DNA had been compared to the DNA profiles of convicted felons in state and federal DNA databanks, without further success. Then, only two weeks ago, detectives received startling news: California’s DNA database had a partial match. DNA identification focuses on thirteen known locations, or “loci,” in the human genome. Each contains chemical sequences that are inherited from one’s parents. The FBI considers it a match if crime scene DNA and suspect DNA have identical sequences at no less than ten loci, and there are no dissimilarities. Some analysts and state labs accept fewer. Now, unrelated persons will frequently match at one, two or even three loci, but the odds that they will share chemical sequences at, say, five or more loci are very low. (For more about DNA identification click here.) A year ago California DOJ launched a familial DNA program, the first in the U.S. California’s DNA repository has DNA profiles for most convicted felons. Until recently the practice has been to report no match with DNA profiles submitted for comparison unless a sufficient number of loci (say, ten) are identical, and there are no dissimilarities. Now, in serious cases, the state will provide the name of any felon in its databank whose DNA profile, although not identical to the submitted DNA(dissimilarities exist at one or more loci) is sufficiently similar to suggest a familial relation. (Pioneered in Great Britain, this procedure has also been adopted by Colorado. It’s under consideration in other states and by the FBI.) Detectives finally had their break. State analysts reported that a DNA profile from the south-central killings likely belonged to a brother or the father of a felon in the state databank. And it got better: that profile wasn’t from just one killing: it was from ten, seven in the late 1980’s and three between 2002-2007. Detectives took on the father, who had lived in south-central Los Angeles for decades, as the likely candidate. Learning that he would be attending a birthday party at a restaurant, an undercover officer bussed his plates, utensils and leftovers. One assumes that yielded a complete, thirteen-loci DNA profile. Analysts compared it to the DNA found on the ten murder victims. There was no question: it was a perfect match. Four days ago LAPD detectives arrested Lonnie Franklin Jr., 57. Although he has an extensive criminal record, including theft, assault, weapons offenses and, as recently as 2003, for car theft, his DNA had never made it into the state database. Without familial DNA, Franklin would have probably never been caught. Dozens of south-central killings lack DNA and remain uncleared. However, detectives found guns in Franklin’s home, and since some victims were shot they’re hoping that ballistics can help. In any event, police are confident that, like Thomas, Franklin committed many more murders than what they can presently prove. At last report, they think as many as thirty more. Not everyone thinks highly of familial DNA. While California Attorney General Jerry Brown and police officials enthusiastically call it a “breakthrough,” the ACLU’s Michael Richter thinks that it could lead innocent persons to be harassed. Winding one’s way through family trees, he worries, “has the potential to invade the privacy of a lot of people.” Richter’s fears seem overblown. Policing is more likely to threaten privacy interests when physical evidence is lacking. Struggling with its own prostitute serial-killer situation, Daytona Beach recently asked gun stores to identify everyone who bought a certain model of weapon during a two-year period (natch, the NRA is crying foul.) That’s intrusive, perhaps unavoidably so. DNA, including familial DNA, can prevent years of fruitless interviews and unproductive searches, to say nothing of more killings and a wrongful conviction. When properly used it’s everyone’s best friend. Of course, good detective work is crucial. Every time that a new maniac comes to light there’s a tendency to go “aha!” and attribute all unsolved homicides to them, risking that some culpable parties will go scot-free. Pressures to clear cases have led to wrongful convictions (remember David Allan Jones?) And as we’ve pointed out before, multiple DNA contributors and mixed DNA samples can yield ambiguous, even incorrect results. In the end, CSI can’t do it alone. Proving that Franklin did more than have sex with his victims will require corroboration, either through statements, other physical evidence (like ballistics) or circumstantially, say, through his whereabouts and activities. It will certainly make for a fascinating trial. We could also do with a bit of introspection. What in the end detectives skillfully resolved was, for victims and their loved ones, solved far too late. Why did it take until 2002 to mount a cold-case campaign? Would we have responded differently had the victims been different or had the killings occurred in a more affluent area? And one must wonder. Three killers (one convicted, two alleged) are locked up. Is there a number four? Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS DNA: Proceed With Caution The Ten Deadly Sins The Usual Suspects Miscarriages of Justice: a Roadmap For Change UPDATES 07/14/10 Jay’s letter to the editor, published in the L.A. Times, responding to a 7/10/10 op-ed: Elizabeth Joh’s fears that "familial" DNA threatens privacy interests are vastly overblown. Ditto for the elaborate vetting mechanism set up by the state to cater to such concerns. Policing is far more intrusive when potentially identifying evidence is lacking. In such cases, detectives will expend hundreds of hours conducting interviews, performing surveillance and serving search warrants, all to narrow the field of suspects. In a current example, Daytona Beach, Fla., police, faced with their own serial killer of prostitutes, have asked area gun stores to name buyers of a particular gun model during a two-year period. Predictably, that’s stirred a hornet’s nest with the National Rifle Assn. Would that they had familial DNA! 07/13/10 Families of Green Sleeper victims had pressed for more police action, but the homicide toll in the 80’s and early 90’s was very high and tough cases tended to be bypassed. 07/10/10 Op-ed in Los Angeles Times warns about the intrusiveness of familial DNA. An article details the extreme measures taken by the state to respond to such concerns, including the use of oversight committees to vet the release of information about the familial match to LAPD. Home Top Permalink Print Share this post Posted 5/30/10 Cops need protection from rifle rounds, not just the ability to shoot back
“Brandon and Bill had no chance against an AK-47. They were completely outgunned. By Julius (Jay) Wachtel. Five days after a father-and-son duo of right-wing extremists opened fire during a traffic stop, killing West Memphis police sergeant Brandon Paudert and officer Bill Evans, chief Bob Paudert, the late sergeant’s grieving father, came to roll call to help his officers deal with the deeply traumatic experience of losing two beloved colleagues. On May 13 sergeant Paudert (left) and officer Evans were on patrol when a white minivan with Ohio plates caught their attention. They pulled the vehicle over and approached its driver, Jerry Kane, 45. What they didn’t notice, at least not in time, was that Kane’s son Joe, 16, had grabbed an AK-47 rifle that his father always carried in the vehicle. Within moments both officers lay dead. The van sped away. It was later spotted in a Wal-Mart parking lot. As sheriff Dick Busby and his top deputy, W. A. Wren approached the vehicle shots rang out, wounding both. Other officers then rushed in and enveloped the van in a hail of gunfire, killing both occupants. A self-styled sovereign citizen, Kane traveled around the midwest coaching homeowners fighting foreclosure. Kane’s services were advertised on an extremist website. Visitors were encouraged to print out letters advising creditors that they were due nothing because the entire mortgage process is a fraud. (There’s even a sample complaint letter to send to the FBI.) Kane also posted debt nullification and patriot videos on YouTube. One, featuring Kane and his son chuckling about “taking a bat” to an IRS agent, carries the father’s prophetic threat: “I don’t want to have to kill anybody, but if they keep messing with me, that’s what it’s going to have to come out...And if I have to kill one, then I’m not going to be able to stop, I just know it.” Kane wasn’t just talking. Recently while driving through New Mexico he encountered a police (“Nazi”) checkpoint. Unable to produce a driver license or identification – as a “sovereign citizen” he didn’t feel that he needed either – he turned a simple ticket into an arrest and jailing. Indeed, as far back as 2004 his antagonistic attitude towards police had so worried an Ohio sheriff that he warned deputies to be wary should they run into him. Kane’s legacy is defended by a number of supporters. With his passing they’ve posted a memorial that praises Kane’s patriotism and questions the official account of his and his son’s demise. 
On April 26 Nye County (Nev.) sheriff’s deputies responded to a call about a domestic argument with shots fired. Diverting to a nearby casino where the woman supposedly went to take refuge, they encountered her male partner in the parking lot. Without warning the man retrieved an SKS semi-automatic rifle from his vehicle and opened fire. Deputy Ian Deutch, 27, was struck and killed by a round that penetrated his body armor. A member of the National Guard, the deputy had just returned from a tour in Afghanistan. Both the AK-47, its commonplace MAK-90 variant (depicted) and the SKS use the 7.62 x 39 rifle cartridge, often called the Russian cartridge because of its adoption by that country’s armed forces. It’s the velocity, hence the energy of centerfire rifle ammunition that explains why an ordinary .30 caliber carbine bullet (1990 fps, 967 ft/lbs.) can penetrate all soft body armor commonly worn by police. Resisting penetration from centerfire rifle bullets requires hard panel inserts. NIJ tests these using conventional and armor-piercing 7.62 mm ammunition. As one might expect, the resulting garments, known as Type III and IV, are far too heavy, hot and clumsy for use on patrol. (Left: Rank Enterprises type III, non-armor piercing vest with alumina panels.) Centerfire rifle bullets cause devastating wounds. According to Di Maio (“Gunshot Wounds,” 2nd. Ed.) as these projectiles traverse tissue they create a temporary, undulating cavity that can be as much as 12.5 times the bullet diameter. “Organs struck by these bullets may undergo partial or complete disintegration. The pressures generated are sufficient to fracture bone and rupture vessels adjacent to the permanent wound track but not directly struck by the bullet.” (p. 171) FBI’s most recent Law Enforcement Officers Killed and Assaulted report indicates that 486 law enforcement officers were feloniously killed with firearms between 1997-2008. Ninety (18.5 percent) were shot with rifles. Forty of these fatalities were caused by 7.62 x 39 ammunition, used in the AK-47, its MAK-90 variant and the SKS. In second place, responsible for twelve deaths, was the .223 caliber, used in the Colt AR-15, Colt Sporter, Ruger Mini-14 and assorted variants. (It’s likely that 7.62 x 39 ammunition figures so prominently because American importers brought in huge numbers of MAK-90’s from China, where they were manufactured for the U.S. market.) Sixty-four percent (309) of the slain officers were killed while wearing body armor. Two-hundred ninety-one died from strikes in unprotected areas, with head shots (115) predominating. One-hundred officers succumbed to wounds in the torso. Of these, 82 were struck in unprotected areas, including armholes and shoulder (38), below the vest (15), above the vest (13) and between side panels (11). Rounds penetrating the vest caused eighteen fatalities. All but one involved rifle ammunition (the sole exception, a death caused by a 9mm. pistol, was attributed to a failure of vest material.) Six were caused by 7.62 x 39 ammo, four by .223/5.56, two each by .30-06 and .30-30, and one each by .300, .308 and 7mm. In 2009 things took a turn for the worse. According to preliminary FBI data 48 officers were feloniously killed, an increase of seven from 2008. All but three fell to gunfire, and a full third (15) to rifles. Officers continue to be imperiled by rifles. In an example earlier this year a 44-year old Pennsylvania man killed his wife, then fashioned a “perch” from which he shot and killed a trooper responding to what he thought was an ordinary domestic quarrel. The weapon used? An equally “ordinary” .30-30. Realizing the threat that they and law-abiding citizens face, police rightfully clamor to carry rifles. Three weeks ago a Los Angeles County sheriff’s deputy on patrol heard rapid gunfire. Fetching his department-issue AR-15, he arrived at a residence just in time to wound and disable a man who had just shot up a home with an AK-47, killing three and wounding two, and was apparently on his way to shoot others. That, too, was a domestic quarrel. Of course, better arming the police isn’t a complete solution. Cops can’t brandish rifles or handle every call like a tactical assault, and should someone be unexpectedly lying in wait, as happened in Pittsburgh and rural Pennsylvania, there may be no opportunity for self-defense. (The West Memphis chief reportedly instructed his officers to henceforth handle traffic stops in pairs, with one carrying a shotgun, but the long-term viability of that approach seems questionable.) The 1994 law in theory banned AK-47s, MAC-10s, UZIs, AR-15s and other assault It’s clear that the firearms industry intends to keep marketing ever more lethal semi-automatic rifles and that nothing to change that is on the horizon. So one would think that the government would be pulling out all the stops to give cops more physical protection. Sadly, one would be wrong. As we pointed out in DNA’s Dandy, But What About Body Armor? practical improvements have been glacial, with soft body armor that’s suitable for patrol now somewhat more comfortable but no more resistant to bullet penetration than twenty years ago. Really, considering what street cops face there ought to be a body armor Manhattan Project, but Federal funding has been stingy and leadership scant. What’s to be done? Well, if you’ve read this far, stop what you’re doing, get on the horn (or keyboard) and press the IACP, PERF, Major Chiefs and DOJ to establish a vigorous, coordinated, well-funded program to improve police body armor, not in another two decades, but tomorrow. With ballistic threats reaching ever-higher levels, we need to give our cops a fighting chance. It’s the least we can do, for them and ourselves. Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS DNA’s Dandy, But What About Body Armor? Reviving an Illusion Shootout at Times Square Oakland: How Could it Happen? There’s No Easy Solution Looking Beyond the Gun Barrel Disturbed Person Long Live Gun Control Gun Control is Dead UPDATES 07/20/10 Armed with a pistol, a shotgun and a .308 rifle, a right-wing extremist on his way to attack the San Francisco ACLU and the Tides Foundation shot it out with the CHP on a busy freeway. 06/08/10 Thirty-two years after bullets from his AK-47 rifle pierced the vest of Austin police officer Ralph Ablanedo, his killer, David Powell, faces execution. 06/02/10 A rewritten California law bans violent felons from possessing body armor. That is already Federal law. California bill Federal law Home Top Permalink Print Share this post Posted 5/2/10 Resource issues, poor oversight and pressures to produce keep plaguing crime labs
By Julius (Jay) Wachtel. “Thank God it got dropped. Now I can get on with my life.” That’s what a relieved thirty-year old man said last month as he left the San Francisco courthouse, his drug charge dismissed, at least for the time being. He’s one of hundreds of beneficiaries of a scandal at the now-shuttered police drug lab, where a key employee stands accused of stealing cocaine to feed her habit. Problems surfaced last September when veteran criminalist Deborah Madden’s supervisor and coworkers became concerned about her “erratic behavior.” Madden was frequently absent or tardy, and when present often stuck around after closing hours. She had recently broken into another analyst’s locker and when confronted offered a flimsy excuse. By November her performance had deteriorated to such an extent that prosecutors thought she was purposely sabotaging cases. Coincidentally, a team of external auditors was in town to review the SFPD laboratory in connection with its application for accreditation. They weren’t informed that Madden had taken leave to check into an alcohol rehab clinic, nor that her sister told a supervisor that she found cocaine at Madden’s residence, nor that a discreet audit of the drug lab’s books revealed cocaine was missing from at least nine cases. Indeed, a formal criminal investigation wasn’t launched until February, when officers searched Madden’s residence. That turned up a small amount of cocaine and a handgun, which she was barred from having under state law because of a 2008 misdemeanor conviction for domestic abuse. When interviewed by detectives Madden conceded filching “spilled” cocaine from five evidence samples. But she had an excuse. “I thought that I could control my drinking by using some cocaine.... I don’t think (it) worked.” Madden otherwise held firm, claiming that sloppy handling by lab employees caused “huge” losses in drug weights. “You just have to check weights of a lot of stuff, because you will see discrepancies. That’s all I’m going to say. I mean, I think you want to put everything on me, and you can’t because that’s not right.” The external reviewers were never told about Madden. Released in March, their report nonetheless chastised the drug lab for being understaffed and poorly managed, with three drug analysts expected to process five to seven times as much evidence as the statewide average, thus affecting the quality of their work. Evidence wasn’t being properly tracked or packaged, precautions weren’t being taken against tampering, and scales and other equipment weren’t being regularly calibrated, making measurements uncertain. Chief Gasçon shuttered the drug lab March 9, throwing a huge monkey wrench into case processing. That, together with Madden’s alleged wrongdoing, led the D.A. to dismiss hundreds of charges. Dozens more convictions are at risk because Madden’s criminal record was never disclosed to defense lawyers, depriving them of the opportunity to impeach her testimony. So far Madden hasn’t been charged with stealing drugs from the lab (she’s pled guilty to felony possession of the small amount of cocaine found in her home.) Really, given how poorly the lab was run, figuring out just how much is missing, let alone what’s attributable to theft and what to sloppiness, may be impossible. In “Labs Under the Gun” we reported on misconduct and carelessness at police crime labs from Detroit to Los Angeles. Here are a few more examples:
In 2009 the National Academy of Sciences issued a blistering report criticizing some forensic science practices as bogus and most others as being far less scientific than what we’ve been led to believe. Virtually every technique short of DNA was said to be infused with subjectivity, from friction ridge analysis (i.e., fingerprint comparison) to the examination of hairs and fibers, bloodstain patterns and questioned documents. That’s a stunning indictment. If analysts’ conclusions have as much to do with judgment as with (supposedly) infallible science, it’s more critical than ever to give them the training, resources and time they need to do a good job. But if resource-deprived, loosey-goosey, production-oriented environments are what’s considered state of the art, forensic “science” in the U.S. still has a very long way to go. Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS UPDATES 07/30/10 Responding in part to the Greg Taylor case (see above) the North Carolina attorney general suspended all bloodstain pattern work at the state crime lab and reassigned its director. 06/29/10 California’s Crime Lab Task Force, created in 2007 to review forensic science in the state and make recommendations, issued a report last November. It has now voted to disband. Report 05/07/10 The SFPD drug lab was permanently closed and its functions given over to private labs. That, said police chief Gascon, should enable the rest of the laboratory to gain accreditation. 05/04/10 Madden case revealed SFPD’s failure to disclose to defense lawyers the criminal and disciplinary histories of upwards of eighty officers, thus bringing countless past cases into jeopardy. Home Top Permalink Print Share this post Posted 4/16/10 Subjectivity can affect the interpretation of mixed samples
“It’s an irony that the technique that’s been so useful in convicting the guilty By Julius (Jay) Wachtel. Some might consider these words unduly alarmist. After all, no less an authority than the National Academy of Sciences has declared DNA to be the gold standard: “With the exception of nuclear DNA analysis...no forensic method has been rigorously shown to have the capacity to consistently, and with a high degree of certainty, demonstrate a connection between evidence and a specific individual or source.” Yet for years there have been troubling signs that interpreting mixed DNA – meaning DNA that’s a blend from different contributors – isn’t as straightforward as some forensic “experts” claim. Consider the case of John Puckett, who was mentioned in “Beat the Odds, Go to Jail,” a post about random match probability, the likelihood that a particular DNA match could have happened by chance alone. In 2003 a partial DNA profile from an unsolved, decades-old rape/murder was compared against the California DNA database. Although the biological specimen was badly degraded and had fewer than the minimum number of markers the state usually requires to call a “match,” what was there was consistent with the DNA profile of Puckett, a convicted sex offender. Although nothing else connected him to the victim or the crime scene, Puckett was tried and convicted. Jurors said they were swayed by a prosecution expert who testified that the probability that the evidence DNA wasn’t Puckett’s was one in a million. It’s since been suggested that the government’s logic was faulty and that the true chance of a mismatch was actually one in three. Since then the trustworthiness of the DNA processing has also come under attack. After sitting on a shelf for twenty-one years the biological sample was badly degraded, leaving only a tiny bit of DNA, and that being a mixture from both the victim and perpetrator. A growing chorus of scientists (and even police labs) warn that such factors can introduce dangerous uncertainties into DNA typing, making matching far more subjective that what one would expect. But let’s turn this over to a real expert. Greg Hampikian, Ph.D (the source of the introductory quote) is professor of biology at Boise State University and director of the Idaho Innocence Project. One of the nation’s foremost authorities on forensic DNA, Dr. Hampikian jets around the globe giving advice and testimony and helping set up innocence projects. He graciously took the time from his busy schedule to give us a primer on DNA and the issues that attend to mixed samples. An interview with Greg Hampikian, Ph.D.
DNA is the repository of all hereditary information. It provides the recipes for all the proteins that can be made by an organism. A stringy acid, it’s comprised of a chain of subunits or “bases,” the chemicals Adenine, Guanine, Cytosine and Thymine. These are linked in pairs, with A only binding to T, and G to C. Nuclear DNA, the kind most often used for identification, is found in twenty-three pairs of chromosomes – one inherited from each parent – that occupy the nucleus of every cell (except mature red blood cells). The complete set of nuclear chromosomes (all 23 pairs) is known as the “genome.” Sperm and egg cells contain only one of each of the 23 chromosomes, and thus have half the DNA of other body cells. Is the full genome used for identification? No. A genome is comprised of millions of linked pairs, far too much information to process efficiently. And it’s not necessary. Instead, identification relies on comparing repetitive sequences (for example AGAT in figure) which can be found at various chromosomal locations, or “loci.” For example, at locus CSF1PO (in chromosome 5) it’s always AGAT. Each locus actually has two STR sequences: one is the “allele” or gene variant contributed by the mother’s chromosome, and one is the allele contributed by the father’s chromosome. In this example, one of the two CSF1PO’s alleles has twelve AGAT repeats. According to population studies alleles at CSF1PO can have between six and sixteen AGAT repeats. Wouldn’t there be many people who have the same number Yes. Numerous persons have the same alleles at one or more loci. But when one compares alleles at thirteen loci, the number required under the FBI’s CODIS system, the probability that a biological sample will be tied to an innocent person (the so-called “random match probability”) is infinitesimally small, far less than one over the population of the Earth. This example demonstrates a perfect match at each of the thirteen loci used by CODIS. Repeat sizes are reported for both alleles. (If both parents contributed the same number of repeats only a single number appears.) So this suspect must be the source of the DNA sample. Yes, most likely, unless they have a twin. Analysts will testify that a match at thirteen loci establishes a positive identification. However, the statistics are less impressive when low amounts of DNA or degradation makes it impossible to type a biological sample at all thirteen loci. CODIS does accept DNA profiles from forensic samples with as few as ten loci, which also yield high match probabilities, but are not unique. Some State systems may allow fewer. Does subjectivity ever intrude into DNA identification? It can. When evidence DNA is from a single source there is general agreement on computing random match probabilities. But interpretation is more difficult when samples are mixed; for example, a rape with multiple assailants. Mixed DNA is like mixing names made with scrabble tiles. For each person you add to the mix, the number of possible names you can pull out soars, so excluding anyone becomes problematic. Mixture electropherograms, the charts used to detect alleles, can become crowded with peaks, making contributors extremely difficult to distinguish. We know from laboratory studies that an And there’s another problem that becomes more of an issue with mixtures – the possibility of bias. Most labs train analysts not to look at suspect profiles before performing mixture analysis. However, since it’s always easier to traverse a maze backwards, the goal of true blind testing is frequently violated. Analysts who have suspect DNA profiles on hand are susceptible to bias and could be less likely to exclude a suspect in a complicated mixture. Also, while most lab protocols require a second, independent analysis, the second analyst is often a close colleague who may have access to the first analyst’s conclusions. What suggestions do you have for the future? There needs to be a lot more study and experimentation with mixed-sample DNA. There’s no accepted standard for interpreting mixed samples, nor is there general agreement among experts as to when to exclude a suspect. Studies by independent researchers are also needed to help labs avoid bias, and enforcement of true independent analysis should be instituted. Defense lawyers and prosecutors are by and large uninformed about these issues, and courts tend to leave it to jurors to work out any apparent contradictions. It’s an irony that the technique that’s been so useful in convicting the guilty and freeing the innocent may wind up leading to wrongful convictions in mixture cases, especially those with very low amounts of starting DNA. Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS Home Top Permalink Print Share this post Posted 11/8/09 WOULD YOU BET YOUR FREEDOM Dog scent evidence comes under fire
By Julius (Jay) Wachtel. “Jag” and “James Bond” are bloodhounds. They drool a lot but they’re nice dogs. And if you believe their caregiver, Fort Bend County (Texas) Deputy Sheriff Keith Pikett, they’re also CSI specialists, with a sense of smell so keen and an intellect so refined that, far more than just following a scent, they can match suspects to crime scenes and accurately convey their findings. Michael Buchanek knows these pooches only too well. One day in March 2006 the retired Texas sheriff’s captain answered his door. It was deputies from his old agency, armed with a search warrant. Buchanek’s neighbor Sally had been found strangled in a field five miles away, and Pikett’s dogs had supposedly followed a scent from the rope used by the killer to Buchanek’s home. Using dogs to track scents is old news. Deputy Pikett and other practitioners of “scent lineups” go it one better. They set up cans in a field. One contains something of the suspect’s, say a shirt, while inside the rest are items belonging to others. Dogs are exposed to a scent from the crime scene and then walked around the cans to see if they alert. Pikett had been running these tests throughout Texas, where his methods were considered good as gold. He did it this time and reported that, yes, a dog alerted on Buchanek’s can. Convinced that their former colleague was a killer, detectives pressed him to come clean. But Buchanek had come clean. He didn’t kill anyone and wasn’t about to falsely confess. Buchanek went through hell for five months. Luckily for him, police finally found the real murderer, who pled guilty. Victoria County Sheriff Michael O’Connor was unfazed. “We did the right thing, and the wrong person wasn’t convicted.” A recent report describes Deputy Pikett’s unusual career. A college graduate with an undergraduate degree in chemistry and a master’s in sports science, Pikett became interested in bloodhounds. By the early 1990’s he was volunteering their services to Texas law enforcement agencies, at first for tracking, then for scent lineups. Although he lacked training in dog handling, followed no protocols and made wild claims of accuracy (his dogs were wrong only once in thousands of trials; they could identify scents many years old) his testimony helped win many convictions. Fort Bend County soon swore him in as a deputy. When a 2002 Texas appeals court opinion declared Pikett a bonafide expert his star rose higher. A Houston citizens’ group named Pikett officer of the year. That niggling little misfire with Buchanek didn’t slow him down. In 2007 he helped Houston police arrest Ronald Curtis for a series of burglaries, and Cedric Johnson and Curvis Bickham for a triple homicide. Curtis spent eight months in jail before the real perpetrator was caught. Johnson was incarcerated sixteen months before he was cleared; Bickham, eight. Pikett’s error-plagued sniff-a-thon continued. In early 2009 he gave Yoakum County authorities what they needed to arrest Calvin Miller for rape and robbery. When Miller was quickly cleared by DNA Pikett’s reputation finally began to tumble. In June 2009 a judge in Pikett’s own county ruled that his methods were unreliable. Bad news traveled fast, and everyone he wrongly fingered wound up suing Pikett and the agencies that used him. Pikett isn’t the only cop charlatan who’s touted canines as ID machines. Pennsylvania trooper John Preston testified in more than 100 cases between 1981 and 1984. In 1981 he used a scent lineup to nail Florida murder suspect William Dillon. One year later his dogs linked another Florida man, Wilton Dedge to a rape. Both were convicted at trial. Decades later DNA proved their innocence; by then Dillon had served 27 years, Dedge, 22. As scent evidence became more popular technology stepped in. Manufactured in California, the STU-100 “scent transfer unit” purports to suck human scent onto a gauze pad that dogs can sniff. This device was used in the investigation of James Ochoa, arrested in a 2005 carjacking after a bloodhound followed a scent from the vehicle to his home. Threatened with a long prison term, Ochoa pled guilty and got two years. Ten months later DNA proved that another person was the real culprit. Ochoa was released and awarded nearly $600,000. The STU-100 figured in the 1998 arrest of Jeffrey Grant for rape (held four months, he was cleared by DNA and awarded $1.7 million), and the 2003 arrest of Josh Connole for a string of arsons (held briefly, he settled for $120,000 after the real perpetrator was caught.) Trained canines can track scents and detect vapors emitted by drugs and explosives. When the proof is in the pudding -- one either finds dope or a bomb, or not -- false alerts (and they do happen) can’t lead to a miscarriage of justice. But using a handler’s interpretation of their dog’s behavior as evidence is extremely risky. Lacking a scientific underpinning and validated performance standards, scent comparisons and lineups are nothing more than voodoo. Dogs aren’t calibrated instruments. As living things they are subject to many influencers, yet unlike their handlers they can’t be cross-examined. Could they have been affected by subtle, perhaps unintended cues from their handler? Might they simply have alerted in error? In 2007, after spending two years locked up because he couldn’t make bail, Riverside County (Calif.) resident Michael Espalin went on trial for setting twenty-one brushfires. The prosecution’s principal witness, junior college biology instructor Lisa Harvey, testified that her bloodhound Dakota tracked a scent from a charred incendiary device to Espalin’s home. Dakota also supposedly matched Espalin’s scent to fire scene vapors collected with a STU-100. According to Harvey the dog could detect scents eight years old. “I don’t know how [scent] stays around for eight years. I just know that it does.” Jurors didn’t buy her testimony, hanging 9-3 for acquittal. Harvey wasn’t used at the second trial, and Espalin was found not guilty. Taking a cue from Deputy Pikett’s victims, he’s now suing both Harvey and the authorities. One can only imagine how deeply taxpayers will have to dig into their pockets this time. Did you enjoy this post? Be sure to explore the homepage and topical index! UPDATES 07/29/10 Wrongful convictions such as those of William Dillon and Wilton Dedge led the Florida Supreme Court to create the Florida Innocence Commission. It will only review cases where innocence has already been established and issue recommendations for improvement. Home Top Permalink Print Share this post Posted 9/20/09 WHAT’S THE D.A. WANT FROM THE SHERIFF? The DNA lab, of course. Or if he can get it, everything.
By Julius (Jay) Wachtel. Orange County (Calif.) District Attorney Tony Rackauckas is a great fan of forensics. So much so, in fact, that he’d like to run a lab. Wouldn’t you know it, there’s one next door! In 2005 Rackauckas got the Board of Supervisors to part with a cool $500,000 so that he could use DNA for property crimes. But rather than going through the Sheriff’s lab he contracted with a private forensics firm to do the work. Why? Apparently the Sheriff insisted on controlling the process, something that Rackauckas wasn’t willing to give up. Only thing is, CODIS, the FBI’s national DNA databank, only accepts profiles from government labs. No problem: Rackauckas entered into an agreement with the Kern County D.A., who runs his own lab, to upload the data. Two years later, flush with an additional $875,000 in county funds, Rackauckas set up his very own databank. It’s accumulated the DNA profiles of several thousand misdemeanants and gang members served with injunctions. One of a smattering of “rogue” repositories around the country, the standalone database isn’t bound by State and Federal rules that limit DNA collection to persons arrested or convicted of felonies. How does Rackauckas get offenders to contribute? Easy -- he “asks.” It’s an offer that many can’t realistically refuse. And now there’s an added inducement: going scot-free! Yes, that’s right. In exchange for $75 and a DNA sample his prosecutors are dismissing non-violent misdemeanors such as petty theft and drug possession. So what if a few cops get “demoralized”? As long as petty violators keep coming, what happens to them down the road seems to be of little public concern. Just like his counterparts in Kern, Sacramento and Santa Clara counties, Rackauckas wants his own lab, or if not the whole enchilada, at least the sexy part, the DNA. His most recent attempt was in June 2008, while the Sheriff’s Department was reeling from the resignation of disgraced former Sheriff Mike Carona. Proclaiming his office as “the only organization capable of harnessing the vast potential of forensic DNA technology for our community,” he urged Supervisors to place DNA under him. And he nearly succeeded. Rackauckas’ move was temporarily short-circuited, first, by acting Sheriff Jack Anderson, who pointed out that he wasn’t consulted, then by the new Sheriff, Sandra Hutchens, who was appalled -- appalled -- at the D.A.’s shameless power grab. A transplant from the far more tightly-wound L.A. County Sheriff’s Department, her recollection of the experience is almost touchingly naive: “I have never experienced anything like it in more than 30 years of law enforcement,” recalled Sheriff Sandra Hutchens, who took over the department in the midst of the battle. “I couldn't get my brain around it, and no one I've spoken with could either.” But the struggle wasn’t over, not by a long shot. By the time that Hutchens’ outrage hit the papers the Supervisors had thrown Rackauckas a consolation prize, appointing him to a newly created Sheriff’s lab oversight panel. Its two other members are Hutchens and the County Administrative Officer, the latter clearly there as a referee. (Hutchens was so put off by the whole experience that she memorialized it in the official Orange County Sheriff’s Blog.) Well, why shouldn’t the D.A. run a lab? In 2005 Orange County resident James Ochoa was arrested for carjacking. Ochoa, who had a drug record, was identified by two victims, and a bloodhound also followed a scent from a baseball cap left in the vehicle to his home. But the O.C. Sheriff’s criminalist who processed the cap and other items recovered from the car determined that the DNA wasn’t Ochoa’s. Her report displeased the head of Rackauckas’ DNA program, Deputy D.A. Carmille Hill, who marched into the lab and demanded that Ochoa not be excluded. Her request was rebuffed. Still, the D.A.’s office wouldn’t drop the charges. Threatened by a judge with a stiff prison term if convicted, Ochoa was unwilling to roll the dice. He pled guilty and got two years. Ten months later the DNA was positively matched to a suspect in another carjacking. Oops! Ochoa got a $550,000 settlement from the cops and $31,700 from the State. Concerns about such unholy influences prompted a National Academy of Sciences panel to suggest that labs be independent of law enforcement. To their credit, though, accredited labs subscribe to protocols specifically designed to prevent such pressures. But prosecutors who think they’re only there to convict could make enforcing safeguards problematic. Knowing just how unyielding D.A.’s can be when they’re convinced they’re right -- and the Ochoa case is a perfect example -- that’s an uncomfortable prospect. DNA is also an expensive tool. A recent study of its use in property crimes estimates the average per-case cost of typing and entering profiles as $374 in Orange County, which processes DNA in-house, and $1147 in Los Angeles, which uses an external lab. (Evidence collection costs aren’t included). When there’s a possible hit DNA costs soar, averaging $13,000 per arrest in Los Angeles and nearly $20,000 in Orange County. And that doesn’t include the expense of creating and maintaining a DNA facility, nor of training and certifying investigators and examiners. Supervisors have dumped more than one and a third million bucks into Rackauckas’ DNA programs. There’s no indication that their generosity was based on a comprehensive review of Orange County’s criminal justice needs. Maybe a study would demonstrate that a back-room DNA operation is a good idea. But giving someone money because of their political juice never is. Ah, your blogger forgot. This is Orange County. Never mind. Did you enjoy this post? Be sure to explore the homepage and topical index! UPDATES 10/5/09 Orange County D.A.’s DNA database has grown four-fold this year Home Top Permalink Print Share this post 
DNA’S DANDY, BUT WHAT ABOUT BODY ARMOR? As lethal threats to police increase, protection languishes -- but there’s hope By Julius (Jay) Wachtel. It’s no surprise that Boston cops feel a chill. With criminals wielding powerful semi-automatic weapons whose rounds can sail through walls (and, as in an incident last week, pierce a mattress and strike a 12-year old girl watching T.V.) you’ve got to wonder why anyone would be so foolhardy as to pin on a badge. Commenting on the tragic event, Boston’s commish bemoaned the proliferation of assault rifles, like the one that wounded the child. They are indeed a significant threat. But there are others. In March a parolee used an AK-type rifle to kill two Oakland SWAT officers who burst into the apartment where he was hiding. Police were there because the man had just shot and killed two patrol officers -- with an ordinary pistol. And it’s not just “real” criminals who we should worry about. Consider the middle-aged Virginia Beach man who, angry over his eviction, opened up with an AK-47 and a MAC pistol, killing two and wounding three before taking his own life. Or the recent massacre in Alabama where a deeply disturbed 28-year old went on a rampage, slaying ten and wounding six. His weapons? A handgun, a shotgun and two assault rifles. You’d think that with all the bullets flying around there would be a massive, Federally coordinated effort to improve ballistic protection for police. But you’d be wrong. Compared to the huge bundles of cash that get thrown at DNA, what’s spent on body armor R & D is puny. Firearms lethality has gone through the roof, yet what beat cops wear today -- when they can, if it’s not too hot -- isn’t much different in comfort and protection than what they wore decades ago. Enough ranting. At the recent NIJ conference your blogger met someone who really knows what he’s talking about. S. Leigh Phoenix (he goes by Leigh) is Professor of Mechanical and Aerospace Engineering at Cornell University. On faculty since 1974, Leigh specializes in composite materials and high performance fabrics. Dr. Phoenix has designed composite overwraps for containers used in the Space Shuttle and space station programs. He’s also been working on ways to measure, predict and enhance the performance of police body armor. If you’re half as interested in keeping cops protected as he is, read on! An interview with S. Leigh Phoenix, Ph.D. How does soft body armor work? When a projectile hits it creates a small pyramid-shaped pocket. Soft armor, which is comprised of many fabric layers, tries to slow down the projectile by pushing back on it at the peak of this pyramid. The best analogy is to a tent, with the central pole representing the projectile. Applying tension to the sides of the tent drives the pole into the ground. As tension on the tent guys increases and the tent’s wall angles become steeper the force on the pole also increases. What happens when a bullet strikes armor? When a continuous-weave fabric is struck by a bullet tension waves fan out in all directions along the yarns, traveling at more than ten times the bullet’s speed. Yarn material behind the waves feeds back towards the peak of the pyramid, allowing a relatively deep pocket to form with fairly steep angles (the steeper the better.) Normally the first few fabric layers will be penetrated, which slows down the projectile a bit. It’s the job of the remaining layers to bring it to a full stop. Yarns used in body armor are more than five times lighter than steel, yet two to three times stronger. They must be very light, stiff and resistant to stretching. These characteristics allow tension waves to travel quickly; they also keep strands from breaking as they’re pulled into the pyramid. Fabrics must also be light, for wearability, and sufficiently flexible to resist crushing and shattering. Some of these factors work against each other, which complicates things. Why are ceramic plates used? Fabric works better when the diameter of the impact patch increases. When high velocity bullets with sharp points strike a plate their tips are blunted. Continued contact with the plate causes mushrooming and deposits debris, further reducing the projectile’s velocity. Current ceramic plates are completely sacrificed in the process.
Is this the ballistic vest of the future? How can we stop high-velocity ammunition? The diagram depicts a hypothetical approach to stopping an armor-piercing rifle round using a combination of ceramic plates and soft armor. Here the “super” ceramic plate (4 mm. layer) has some flexibility and initially blunts the projectile, causing the lead inside the tip (dark area) to splay out. As the bullet continues its copper jacket slides forward and mushrooms and the interior steel core (large pencil-like region behind the lead) tries to push through, but you want to blunt that too, which takes a little more distance. A final fabric panel brings the slowed projectile to a full stop. This concept illustrates a basic tradeoff: you need distance to stop a projectile, but you don’t want to fill the needed space with heavy materials or the vest will be too heavy to wear. Impressive. But ceramics are hot and heavy. Are there alternatives? With research and testing it could be possible to develop considerably lighter ceramics that can better withstand the rigors of the job There’s another approach. At present all ballistic vest yarn is continuous, allowing material to be sent to the impact point. However, the first few layers are usually penetrated, accomplishing little other than some projectile slowing and blunting. It turns out that a single layer of unwoven yarn can be hit at much higher speed without breaking because it’s not loaded down by the drag of all the other yarns around it, especially as the pyramid deepens. In fact, a two or three inch length of the very strongest yarns can be hit at up to 2500 fps without breaking, even with a pointed-tip projectile. I’ve given thought to using discontinuous yarns -- small segments, say two inches long -- for the first few layers, which instead of snapping would form a wad around the projectile’s nose as it plows through. That would increase the bullet’s frontal area, slowing it down and helping the fabric underneath do its job. Naturally, it would require a lot of development and experimentation to optimize fiber lengths and combinations. Calculations suggest that it could work with velocities in the 2400 fps range, which covers some rifle threats. Otherwise there will be a need for some ceramic, though maybe a lot thinner than what’s now used. Officers are dying from head shots. What about helmets? Helmets have a couple of limitations. First, they must float a distance from the skull so there’s room for deflection. They also lack wide, flat surfaces that can be covered with material to pull into the pyramid. So one can’t just take ballistic vest technology and apply it to helmets. But I think that it’s possible to develop a helmet that’s effective against handguns and light enough to wear on patrol. What’s happened in the last twenty years to improve ballistic protection for police? Really, not that much. Kevlar has been tweaked, yielding stiffness/strength combinations that marginally improve its velocity performance. A few new fibers have come out. Zylon, which was used on vests and seemed superior, is now on hold due to degradation concerns. Another fiber, M5, potentially much stronger than Kevlar, hasn’t gone commercial because of manufacturing or other problems. Two ultra high-strength polyethylene fibers, Dyneema and Spectra, are 50 percent lighter than Kevlar and just as strong and stiff. They’ve been used in cockpit doors. They may still be too expensive for wide use in vests but perhaps ideal for the helmets mentioned earlier. Private industry has a big stake in body armor. Can’t we expect them to lead the way? Body armor makers sell all they produce, so I don’t see major improvements happening under the present commercially-driven system. I know of an example where extensive manufacturing changes could make yarns stronger, but the company isn’t convinced that the investment would pay off financially. Manufacturers also hold their work very close to the chest. They have their own ideas, needs and priorities and collaborating with them is generally difficult, though I’ve been fortunate in one case. What about Government funding? Funds from government agencies like NSF and the Army are available if you’ve got the right buzzwords, meaning nanotech, biotech, carbon nanotube structures and so forth, but a lot of what gets proposed and funded is unlikely to lead to useful applications in the near term. Funding systematic work on something practical like body armor is difficult because those making the decisions (who never get shot at) consider the topic old-hat and think that the problems have been addressed and solved, which they certainly have not. Federal law enforcement research dollars are spread very thin, especially when it comes to academic institutions. DOD concentrates on vehicle armor. Their successes are classified, making them unavailable to university researchers. Where should we go from here? A lot could probably be done working with present fiber materials, tweaking them with improved processing to increase their strength without changing the basic chemical structure. You could change how fabrics are designed, say, by developing hybrid layered structures. Coming up with an altogether new material could yield big improvements, but we should not underestimate what clever manipulating can do. To push the frontiers not just as a scientific exercise but with the objective of making significant, practical improvements requires a consortium of knowledgeable, technically-adept researchers who appreciate all the issues, including the need for comfort so that body armor actually gets worn. In other words, one must work on the whole package. We need resources for research and experimentation. We also need an agency or a group of agencies that would host a long-term, comprehensive effort to develop a new materials system that would yield armor that is more protective and comfortable. Source for figure: S. Phoenix and P. Porwal, “A new membrane model for the ballistic impact response and V50 performance of multi-ply fibrous systems,” International Journal of Solids and Structures (vol. 40, 2003, p. 6724) Did you enjoy this post? Be sure to explore the homepage and topical index! OTHER POSTS IN THE 2009 NIJ CONFERENCE SERIES: Science is Back. No, Really! Ignorance is Not Bliss Slapping Lipstick on the Pig Part I Part II Part III Home Top Permalink Print Share this post Posted 2/22/09 Putting the “science” back in forensics won’t be simple
By Julius (Jay) Wachtel. Three years in the making, the National Academy of Sciences’ anxiously-awaited “Strengthening Forensic Science in the U.S.: A Path Forward” is finally in, and it doesn’t paint a pretty picture. Although it’s clearly a product of compromise -- the National Institute of Justice reportedly opposed funding the study, then demanded a say in the conclusions -- the report has more than enough meat left on its bones to threaten the interests of labs and self-styled “experts” across the country. At its most general, the study urges that forensic science live up to its name. Processes used to analyze evidence and make comparisons should be objective, set out in detail, reproducible by others and, as a topper, yield conclusions whose certainty can be accurately estimated, a requirement that places a big question mark next to virtually every identification technique short of DNA. Lamenting the ease with which junk science weasels its way into court, the report’s authors advise establishing a “National Academy of Forensic Science” that would guide research, set standards and certify labs and examiners. To keep unholy influences at bay, they also urge that labs function as independent entities outside the control of both law enforcement and private interests. It’s a heady agenda that runs head-on into how forensic science is presently organized in the U.S. While many of the more ambitious objectives stand little chance of being implemented in the near term, the report’s disparaging views on some popular forensic matching techniques will surely be welcomed by the defense bar. Here is some of what Chapter Five, “Descriptions of Some Forensic Science Disciplines” has to say:
Crime scene fingerprints are often of poor quality, leading to subjective judgments that occasionally prove wrong. If the error is a false positive (saying that two prints match when they do not) such as what happened in the Brandon Mayfield case, and more recently at the LAPD crime lab, the consequences can be catastrophic. Meanwhile the identification community resists objectivizing its methods; for example, by using point systems based on minutiae, presumably because setting thresholds would yield fewer matches. When examiners testify that two prints were deposited by the same person they do so to an absolute certainty. Yet, as the report points out, no judgment can be that “certain.” Indeed, it’s the ability to quantify the probability of error that’s the hallmark of a true science. Whether fingerprinting can be raised to that level remains to be seen. More hope is held out for comparing fibers, whose chemical composition can be analyzed with existing tools and protocols. However, since little is known about the effects of manufacturing and wear, reliably matching fibers to specific garments or carpets remains out of reach. What gets admitted into evidence is ultimately up to a judge. Federal practice, on which most State laws are modeled, is set out in Rule 702, Federal Rules of Criminal Procedure, “Testimony by Experts.” Before admitting scientific evidence, judges must determine whether “(1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.” In the era of C.S.I., with an entrenched forensic establishment that has elevated itself to a near-religion, not even an epidemic of wrongful conviction has managed to slow the choo-choo train of junk science. On the other hand, should defense lawyers take notice of the report, many of today’s quasi-scientific forensic techniques will pass into the realm of voodoo, where they’ve always belonged. Here’s to their speedy demise. Did you enjoy this post? Be sure to explore the homepage and topical index! ONLINE VIDEO “How CSI Went Awry” -- William Thompson, Ph.D., UC Irvine, discusses findings of NAS report and its implications for the future of forensics (71 min.) RELATED POSTS UPDATES 07/30/10 Responding in part to the case of Greg Taylor, an innocent man who spent 17 years in prison for murder, the North Carolina attorney general suspended all bloodstain pattern work at the state crime lab and reassigned its director. 04/28/10 Frank Sterling was convicted of murder in 1982 thanks to a confession extracted under duress and with the use of hypnosis. He was freed today after DNA proved that the original suspect, who went to prison for killing a child two years later, was guilty. NY wrongful convictions Report 03/15/10 Donald Gates served 28 years for rape/murder based on an FBI analyst’s testimony that one of his hairs was found on the victim. Then DNA proved him innocent. DOJ, who knew since 1997 of such problems, is reviewing the work of six analysts. More than 100 cases are involved. 01/19/10 As the FBI continues reviewing 2,500 cases where analysts used a now-discredited bullet lead comparison technique, judges continue releasing persons convicted on their testimony. 09/10/09: Disturbed by the conclusions of the NAS report, Senators seem to support more funding for forensics research and possibly setting standards for crime labs and analysts. 08/24/09: Financial concerns and opposition by groups such as the National District Attorney’s Association make it unlikely that Congress will create an independent forensics oversight panel 05/17/09: Scientists react to N.A.S. report Home Top Permalink Print Share this post Posted 10/12/08 Commonly accepted techniques may lack scientific value By Julius (Jay) Wachtel. On February 17, 2004 Texas inmate Cameron Todd Willingham was strapped to a gurney and given a lethal injection. He had been convicted of arson and murder in a 1991 house fire that killed his three daughters. Evidence against him included the statement of a jailhouse informer who said that Willingham confessed and scientific testimony by the State Fire Marshal’s office that the fire was deliberately set. Willingham protested to the very end that he was innocent. Now it looks like he might have been right. In August 2008 the Texas Forensic Science Commission agreed to review a 2006 report by five nationally recognized fire experts who refuted the “arson indicators” cited by Texas authorities at Willingham’s trial and said the fire was accidental. One of these indicators, crazed glass, was once thought to be evidence of a superhot fire fed by accelerants. It’s now known to be caused by spraying water on hot glass. According to the experts, another indicator, burn patterns in the floor suggestive of accelerants were meaningless in a fire that burned as hot as the one that destroyed Willingham’s home. And so forth. In addition the Commission will also be considering the wrongful conviction of Ernest Ray Willis, who spent 17 years on death row for an arson/murder much like the Willingham case. While preparing to retry Willis (his case had been overturned on technical grounds) the prosecutor concluded that the State Fire Marshal’s “scientific” testimony was mistaken and that the fire was accidental. Willis was released. On March 11, 2004 terrorist bombings in Madrid train stations killed 191 and injured two-thousand more. During their investigation Spanish police recovered fingerprints from inside a bag of unexploded detonators and furnished images of the prints to the FBI. FBI fingerprint examiners digitized the images and ran them through the national database. They soon identified the prints as belonging to Brandon Mayfield, a Portland attorney who was Muslim and once represented a suspected terrorist in a civil case. Confident in their conclusions, the FBI ignored Spanish investigators who insisted that the prints didn’t match and that the bombers were Moroccan terrorists with no known connection to Al Qaeda or the U.S. On May 6, 2004 the FBI arrested Mayfield as a material witness in the bombings and searched his residence. Within days Spain positively identified the man who left the prints as a known Algerian terrorist. Two weeks after arresting Mayfield the FBI let him go. He got $2 million in taxpayer cash for his troubles. How could this happen? Found or “latent” fingerprints are nothing like the complete, neatly inked fingerprints taken from job applicants and persons arrested for crimes. Instead, they’re often fragmentary, smudged, distorted and overlapping, which can make it difficult for examiners to identify the “minutiae”, the islands, dots, bifurcations and ridge endings on which comparisons rely. (In this example, a “good quality” latent is on the left, and the same finger inked is on the right.) Every State and the FBI have large repositories of digitized fingerprint cards. The FBI holds prints for nearly one-hundred million persons, split about evenly between arrestees and applicants. Running recovered prints through these databases yields cards with the closest matches. It’s up to local examiners to order those of interest and microscopically compare them to the latent to see if there’s a fit. Generally at least seven minutiae must match, while only one inconsistency disqualifies. Extrinsic factors such as investigator’s suspicions must never intrude on an examiner’s judgment; if they do, as what apparently happened in Mayfield, the examiner (in the FBI’s case, several examiners and their boss) might mistakenly “find” matching minutiae in the latent that simply aren’t there. Firing a weapon leaves markings on bullets and cartridge casings that are supposedly unique to that particular gun. If cartridge casings or bullets found at a crime scene or extracted from a body have a sufficient number of identical markings and no inconsistencies examiners will testify that they were also fired by that gun. That’s the belief. However, a recent report by the National Academies concludes that while “one can find similar marks on bullets and cartridge cases from the same gun,” the assumption that only that gun could have produced those markings “has not yet been fully demonstrated.” Even if we believe that ballistics evidence is reliable, humans aren’t. In this comparison a recovered bullet in excellent condition is on the left, and a bullet test-fired through the same gun is on the right. We can see that the striations left by the barrel line up perfectly. In the real world, though, bullets are often deformed and fragmented, making comparison difficult. Detroit PD’s lab was recently shut down after State Police auditors found three “false positives”, cases where examiners mistakenly reported a match that didn’t exist. Why did the State come in? After a recent murder conviction a retired State firearms examiner conclusively demonstrated that shell casings found at the crime scene came from at least two weapons, not one as the police lab claimed. The judge dismissed the case, which will be retried. Everyone’s heard of Phil Spector, the celebrity murder defendant whose first trial ended in a hung jury (his retrial will begin any day.) There’s no disputing that the victim, Lana Clarkson, died from a bullet discharged while a gun barrel was in her mouth. Spector claims that he was six feet away when the gun went off. His claim was propped up by blood spatter expert Stuart James, who said that droplets could travel six feet. But Sheriff’s criminalist Dr. Lynne Herold, who admitted she had taken one of James’ courses, said no, that their range was at most three feet. That little duel is likely to replay itself. Meanwhile, what are we to think of blood spatter evidence? Is it meaningful or not? Maybe CSI isn’t all that it’s cracked up to be. Physical evidence has to be collected, bagged, tagged and interpreted by fallible humans who can slip at any stage of the process, damaging the goods, making them out to be what they’re not, or inferring that they mean something they don’t. It’s happened with arson, fingerprints, ballistics and blood spatter. Last week we mentioned that goofs leading to wrongful convictions have even happened with DNA, which is particularly scary given its aura of infallibility. According to a recent article in the New York Post, the National Academy of Sciences is expected to shake things up this December with a report that will question the value and accuracy of accepted forensic techniques. Not to worry, Joe Friday. Looks like shoe leather will be in style a while longer. Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS RELATED ARTICLES UPDATES 03/15/10 Donald Gates served 28 years for rape/murder based on an FBI analyst’s testimony that one of his hairs was found on the victim. Then DNA proved him innocent. DOJ, who knew since 1997 of such problems, is reviewing the work of six analysts. More than 100 cases are involved. 01/19/10 As the FBI continues reviewing 2,500 cases where analysts used a now-discredited bullet lead comparison technique, judges continue releasing persons convicted on their testimony. 10/07/09 Texas Innocence Project calls dog scent lineups “junk science” after DNA clears cop of murder 08/31/09 A New Yorker piece concludes that Cameron Willingham was innocent 08/17/09 Israeli scientists manipulate DNA to create fake blood samples 03/16/09 A prosecutor said that 147 cases of Detroit PD lab work so far identified as questionable is only “the tip of the iceberg” 01/15/09 False fingerprint matches that resulted in at least two mistaken arrests have led to a review of nearly 1,000 cases in which two LAPD examiners were involved. Home Top Permalink Print Share this post Posted 10/5/08 Can police crime laboratories be trusted?
“Of the 33 adjudicated cases from the Wayne County Prosecutor’s Office that were reanalyzed, 3 exhibited Class I inconsistencies. In total, this equates to approximately 10% of the completed firearms cases having significant errors. On average, the DPD firearms unit analyzes 1,800 cases per year. If this 10% error rate holds, the negative impact on the judicial system would be substantial, with a strong likelihood of wrongful convictions and a valid concern about numerous appeals.” By Julius (Jay) Wachtel. These words aren’t from do-gooders wringing their hands about possible miscarriages of justice. They’re from an official September 2008 report by the Michigan State Police setting out the preliminary findings of an audit of the Detroit crime lab’s firearms unit. Firearms examiners often test-fire recovered guns hoping to link them to crimes. Firing a weapon leaves markings on bullets and cartridge casings that are supposedly unique to that specific gun. If a sufficient number of identical marks are present in the same locations on cartridge casings or bullets recovered at a crime scene (or extracted from a body) it’s evidence that they were fired by the same gun. Naturally, great care must be taken to insure that there are enough points in common. It’s also critical that there are no dissimilarities; just like in fingerprinting, only one inconsistency rules out a gun as being the source of a particular bullet or cartridge casing. Michigan State Police auditors reviewed 200 firearms cases. Nineteen had “either Class I or Class II inconsistencies”. A Class I error means that an examiner erroneously declared a match. Such “false positives” can obviously lead to a wrongful conviction. In Class II errors, “false negatives,” a match was overlooked, possibly letting a guilty person go free. Detroit PD responded by shutting down the entire crime lab -- not just the firearms unit -- and turned over all forensic analysis to the State. It then set out on the unenviable task of reviewing past cases involving testimony by firearms examiners. There was little choice, as defense attorneys immediately announced they would begin questioning everything the lab has ever done. Meanwhile displaced lab employees mounted a protest, claiming that problems in the firearms unit did not affect the good work the lab was doing elsewhere, from fingerprint comparison to DNA. Their view was undercut by the words of their own superior, who in a September 2008 memo reported that the lab’s overworked and underpaid staff was running four-thousand chemistry and biological cases behind. (She retired when the lab closed.) Alas, Detroit isn’t unique. In November 2002 Houston shut down the DNA section of the police crime lab after an investigation by a TV station revealed a history of shoddy work. A subsequent audit of the lab’s DNA work disclosed “a wide range of serious problems ranging from poor documentation to serious analytical and interpretive errors that resulted in highly questionable results being reported by the Lab.” Issues were also reported in firearms, trace evidence and drug analysis. What’s worse, at least two cases of wrongful conviction have been attributed to Houston DNA errors. Josiah Sutton served four and one-half years of a 25-year term after the lab incorrectly determined that his DNA was present in a sperm sample. George Rodriguez served seventeen years of a 60-year term; his conviction was due in part to bad witness ID, in part to a mistaken failure to exclude him as a DNA donor, and in part to an incorrect conclusion that a hair found on the victim was likely his. That’s not all. In January 2008, one and one-half years after the Houston lab’s DNA section reopened, its new supervisor was allowed to resign for helping staff members cheat on proficiency exams. (Amazingly, she was then hired to run the State lab’s DNA section.) It happens to the best of labs. In May 2005 a grievous analytical error at the Virginia State crime lab, reportedly one of the nation’s finest, prompted Governor Mark Warner to order the re-examination of 150 DNA cases. His move was prompted by a 1985 case, where a prisoner on death row, Earl Washington, came within nine days of being executed before a team of pro-bono defense lawyers finally got him a stay. In 1993, with the threat of execution again looming, a DNA test (which the State partly botched) got Washington’s sentence commuted to life imprisonment. It would take another seven years and a correctly performed DNA procedure to conclusively clear Washington and identify the guilty party. By the time he was finally released in 2000 the innocent man had spent seventeen years behind bars. Mismanagement and lax quality control have vexed crime laboratories for decades. O.J. might have never been in the position to pull the shenanigan in Vegas except for a lab goof. (His acquittal in the 1994 murder was in large part due to evidence of widespread contamination at the LAPD crime lab.) But trying to keep labs on the straight and narrow with after-the-fact controls such as accreditation visits is a loser’s game. As long as facilities are tidy, paperwork is in order, equipment is in proper repair, manuals are up to date and everyone on staff is certified a “pass” is virtually guaranteed. Everyone wants to solve crime through science and technology. But as auditors in Houston pointed out, running a good lab is an expensive proposition. When resources are limited -- and when aren’t they? -- it’s easy to wind up with a production-oriented pressure cooker that encourages shortcuts and sloppy work. Throw in a dash of unskilled examiners and a pinch of poor oversight and it’s a recipe for disaster. Next week we’ll look at issues in forensic techniques, from fingerprinting to ballistics. Stay tuned! Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS UPDATES 06/29/10 California’s Crime Lab Task Force, created in 2007 to review forensic science in the state and make recommendations, issued a report last November. It has now voted to disband. Report 06/23/10 Beset by understaffing, lack of support, no training and poor equipment, Houston PD’s fingerprint unit remains in bad shape even after an infusion of money and hiring external contractors. Blame for the neglect was placed on distractions caused by problems elsewhere in the crime lab. 03/15/10 Donald Gates served 28 years for rape/murder based on an FBI analyst’s testimony that one of his hairs was found on the victim. Then DNA proved him innocent. DOJ, who knew since 1997 of such problems, is reviewing the work of six analysts. More than 100 cases are involved. 03/04/10 An analyst’s incorrect testimony that blood was found in a vehicle is leading to a reexamination of thousands of old Georgia lab cases to check their accuracy. Related post 01/19/10 As the FBI continues reviewing 2,500 cases where analysts used a now-discredited bullet lead comparison technique, judges continue releasing persons convicted on their testimony. 12/18/09 Deceased NY State analyst falsified reports for fifteen years to cover up his incompetence, throwing hundreds of cases in doubt and creating questions about the rest of the lab. Report 04/08/09 Jarrhod Williams, convicted of two counts of first-degree murder but granted a new trial because the Detroit PD crime lab botched the ballistics was convicted again. 01/14/09 LAPD fingerprint problems lead to review of nearly 1,000 cases 10/18/08 LAPD fingerprint examiners criticized for serious lapses, including mistaken matches Home Top Permalink Print Share this post Posted 9/28/08 Is brain scanning the new polygraph? By Julius (Jay) Wachtel. Hey, Dick Tracy: don’t knock yourself out pounding the pavement! There’s a far easier way to solve a whodunit. Have a suspect put on a helmet full of electrodes. Then show him a series of photos, including some neutral pictures and some of the crime scene. Looking at the photos will stimulate brain activity, sending electrical signals through the helmet to an EEG machine. You’ll wind up with an electroencephalogram, a chart that identifies the precise regions of the brain that the images stimulated. Now look closely: if “experiential” areas of the brain “light up” for the crime scene photos, but not for the others, you’ve got your man. Hook him, book him and reward yourself with a trip to Winchell’s! If not, move on to the next chump. According to an emerging technology known as BEOS, for “Brain Electrical Oscillations Signature,” there are places in the brain that store memories of events that one actively experienced, not just passively observed. Proponents claim that’s what makes it possible to distinguish between a killer and someone who merely discovered a body. Peddled in the U.S. by companies including No Lie MRI and Cephos for use in everything from commercial disputes to intelligence, the technology supposedly far surpasses polygraphy in accuracy. In fact, it was recently used by prosecutors as evidence in a murder case in Mumbai, India. To clear herself, a woman charged of poisoning her husband volunteered for a BEOS test. It wasn’t a wise choice -- the test said she did it. Oopsie! No Lie and Cephos aren’t alone. A competing technology known as Brain Fingerprinting also gauges the brain’s electrical reaction to visual and aural stimuli, but in a fundamentally different way. Developed by neuroscientist Larry Farwell, it relies on a well-established neurological phenomenon, the so-called “P300 wave,” an involuntary electrical impulse that our brains generate whenever we recognize (have an existing memory of) something, be it an object or a piece of information. For example, tell a suspect that they’re about to see a picture of the murder weapon, but don’t say what it is. Strap on the helmet (on them, not you) and run a series of slides, say, a gun, a knife, a baseball bat, and what was actually used, Auntie’s embroidery needle. If he emits a P300 wave when the needle comes up, and only when it comes up, have a scrumptious jelly-filled gut buster on us! If not, move on. To his credit, Farwell readily admits that the process has limitations; it won’t work, for example, if word of the needle got out to the public, since everyone would then react to its image. But he claims that when investigators come up with something only the real perp knows, the technology is virtually foolproof. Alas, neither BEOS nor Brain Fingerprinting have made it into the judicial mainstream. (Brain Fingerprinting claims otherwise, but the episodes cited in its website hardly set a precedent.) According to the landmark Frye decision, before expert scientific testimony can come into court its validity must be widely acknowledged. But the kingdom of the nerds remains highly skeptical. As J. Peter Rosenfeld, a pioneer of using brain waves in lie detection points out, there’s a lack of peer review and replication, the sine qua non of scientific acceptance. Other neuroscientists feel likewise. “Well, the experts all agree,” says Michael Gazzaniga, director of a UCSB mind-research center, referring to BEOS. “This work is shaky at best.” Unlike the polygraph, which records physiological changes supposedly brought on by the stress of lying, neither BEOS nor Brain Fingerprinting directly measure deception. They’re also far more passive, as no interaction is required between tester and subject. Keeping the two apart prevents contaminating the results, but it also means that EEG technicians won’t get what polygraphers really aim for. It’s the lie detector’s dirty little secret that its real worth isn’t in the squiggles it produces -- the National Academy of Sciences considers those close to worthless -- but on the incriminating statements, admissions and full-blown, tearful confessions that scared, stressed-out subjects occasionally make while in the chair. But it’s not just about ends -- means are also important. The privacy and liberty implications of brain-wave technology are (pardon the pun) mind-boggling. Just to mention one issue, polygraph subjects are free to clarify and challenge each question before answering. In contrast, EEG screening is purely passive, allowing sneaky administrators to venture into areas far afield of their manifest purpose without the test subject realizing or having a realistic opportunity to refuse. What’s more, we might not even know that we’re being checked out. Technology now in development allows the remote detection of “anxious” people. FAST, an acronym for “Future Attribute Scanning Technology” (how’s that for an Orwellian nightmare) uses cameras and sensors to screen passers-by for hostile thoughts and intentions, assessing characteristics such as facial expressions and pulse rate. Imagine the false positives that a gaggle of ACLU lawyers would produce! Well, we’ve got a label for these precious new techniques: Mindboarding. Feel free to use it, but be sure to say that you saw it first on PoliceIssues.com! Did you enjoy this post? Be sure to explore the homepage and topical index! UPDATE (3/13/09): Newsweek column by Sharon Begley, “Of Voodoo and the Brain,” challenges the scientific basis of brain imaging Home Top Permalink Print Share this post Posted 5/11/08 DNA random match probabilities may be overstated By Julius (Jay) Wachtel. Looking for a growth industry? Think genetics. With more than one million profiles, California’s DNA databank is the third largest in the world, trailing only those of the FBI and Great Britain. At its 1990 debut the GoldenState’s database only kept track of sex offenders, but it has since expanded to include everyone convicted of a felony. What’s more, starting next year DNA specimens will be collected from every adult arrested for a felony, a move that should increase the databank’s size by 390,000 profiles each year. When DNA got its start there weren’t databanks, so police had to have someone in mind to make crime scene DNA useful. Now it’s possible to run unknown DNA through massive databanks like California’s hoping for a “cold hit.” A recent example is the case of John Puckett, a previously convicted rapist who is appealing his conviction on a thirty-year old rape/murder. An expert testified that there was only one chance in 1.1 million that the match between Puckett’s DNA and the crime scene sample could have happened at random. With a probability of error that low, prosecutors suggested there was only one explanation: both samples came from the same source. Not unexpectedly, jurors agreed, sending the 70-year old to prison. Since the human genome is exceedingly large, DNA is only typed at thirteen known places (“loci”) in the strand. Each location has two chemical sequences (“alleles”), one inherited from each parent. Scientists have determined how often specific loci/allele combinations occur in different populations, such as Caucasian males. Single combinations are commonplace and can be present in one out of every three or four persons. Multiple loci/allele combinations occur less frequently. In this example the probability of randomly selecting a DNA profile with four specific loci/allele combinations is 14 in 100,000. Just like with fingerprints, a single dissimilarity between DNA profiles means that they’re not from the same person. If no differences are observed a sufficient number of identical loci/allele combinations must be present to suggest that they have a common origin. How many is enough? There’s no set answer. Five and six loci/allele combinations can yield probabilities of a random match in the one-in-a-million range; while seven or more can generate probabilities in the hundreds-of-millions, billions, trillions or even quadrillions. (For an online tool that lets users run a sample profile, click here.) When a suspect is independently developed a subsequent DNA match obviously carries enormous weight. Still, the DNA match alone is not a probability of guilt -- it’s an estimate of the likelihood that DNA drawn at random will match the profile of crime scene DNA. (Probability of guilt requires that all other pertinent factors be considered. This requires use of Bayes’ theorem.) Random match probabilities also assume that we only draw once from a population. But that’s not what happens in cold hits. No one knows whether the match that cooked Puckett’s goose came on the computer’s first draw or last (at the time California had 338,000 DNA profiles online.) Had the expert witness followed the recommendation of the National Academy of Sciences he would have multiplied the random match probability of one in 1.1 million by the number of draws (338,000), yielding a true random match probability -- in effect, the chance of mistakenly identifying an innocent person -- of one in three. Interestingly, the expert told a reporter that he didn’t mention the adjustment, which he agreed was a superior approach, because the judge wouldn’t allow it. After the trial jurors said that the probability of one in 1.1 million was a key factor in deciding to convict. Asked if correcting it might have affected the verdict a juror said, “of course it would have changed things. It would have changed a lot of things.” Bigger DNA databases will yield more matches. While that seems beneficial, more profiles mean more draws, so the probability that matches may be caused by chance will increase. Of course, random match probabilities with denominators that approach or exceed the population of the U.S. or the planet will remain noteworthy. In any event, understating the probability that a match might point to the wrong person is no solution. At least one expert has already warned that an invaluable tool for freeing the innocent -- DNA -- could inadvertently become an instrument of wrongful conviction. Only days ago Puckett’s appeal was argued before the California Supreme Court. Its decision is expected soon. In the meantime keep away from the lottery. The probability of hitting it is so low that if you do, it could be evidence that you fixed it! Did you enjoy this post? Be sure to explore the homepage and topical index! RELATED POSTS UPDATES 02/24/10 Puckett case featured in the Washington Monthly 06/16/08 Ruling in People v. Nelson, where the random match probability in the general population was in the quadrillions, the California Supreme Court decided it’s permissible to introduce it even though the match was against a database. The “database probability” can also be introduced. 07/20/08 Arizona DNA data challenges rarity of DNA profiles, especially when fewer than 13 loci are available for comparison 05/05/08 Ninth Circuit rules on DNA random match probability, calls its misuse a due process violation. Home Top Permalink Print Share this post Posted 12/7/07 Lab goofs and dueling “experts” give forensics a black eye By Julius (Jay) Wachtel. New York State’s Inspector General recently recommended that criminal charges be considered against the retired director of the New York Police Department’s crime lab and three former analysts for botching thousands of drug tests in 2002. Investigators claim that analysts took shortcuts when analyzing large seizures, falsely certifying that every container of suspected drugs was tested, and that managers who suspected something was amiss turned a blind eye. The lapse caused NYPD to start re-examining 3,000 individual drug tests last March. However, by that time more than 700 had been destroyed, bringing every conviction based on those tests into question. Problems at crime labs are nothing new. In June 2007 an investigative panel cast doubt on thousands of convictions in Houston, calling its police lab deficient “across the board,” with serious errors in ballistics, drugs, DNA and serology. The damage was not merely hypothetical, with mistakes responsible for at least three wrongful convictions: Ronald Taylor, who served 14 years because the lab missed finding the real perpetrator’s DNA on a bedsheet, and George Rodriguez and Josiah Sutton, who served 17 and 4 ½ years respectively due to faulty serology. Nearly two-hundred other cases are on review. In May 2005 Virginia’s Governor ordered a review of 150 cases processed through the State’s crime lab after two botched DNA tests nearly led to the execution of Earl Washington, Jr., who served 18 years after being wrongfully convicted of rape. Washington was only nine days away from lethal injection when discrepancies in the case prompted the prior Governor to commute his sentence to life imprisonment. A properly conducted DNA test later proved that the perpetrator was an already-convicted serial rapist. Auditors attributed the Virginia lab’s sloppy work to pressures to increase productivity. A Federal civil jury awarded Washington $2.25 million in compensation. Two months after terrorists bombed a Spanish train, leaving 200 dead and 1,400 injured, FBI agents arrested Portland attorney Brandon Mayfield as a material witness. FBI fingerprint examiners said they matched Mayfield’s fingerprints to latent prints found by Spanish police on a bag of unexploded detonators. Confident that they had the right man (Mayfield is Muslim and represented a suspected terrorist in a civil action), the Feds refused to believe Spanish experts who insisted that the prints were not Mayfield’s. A chastened FBI eventually apologized when Spanish investigators positively identified the fingerprints as belonging to an Algerian suspect. It’s not just lab goofs that give forensics a black eye. In the recent Phil Spector trial renowned experts argued about, well, everything -- from the cause of the injury to the victim’s tongue, to how far blood spatter can travel, to whether the victim could have coughed after being shot. Spector’s trial is remarkably similar to the 2004 murder trial of Idaho resident Craig Perry, who insisted that the uncle he was accused of shooting committed suicide. Thanks to blood spatter expert Stuart James, the same witness who raised enough doubt to hang Spector’s jury, Perry won an acquittal. (Demonstrating the whimsical, musical-chairs aspect of forensic “science,” another of Spector’s experts, Dr. Vincent Di Maio, testified against Perry. Back then Di Maio was still Chief Medical Examiner for San Antonio and working for prosecutors.) A litany of lab disasters, dueling experts, wrongful convictions and bizarre acquittals (O.J. and Robert Blake come to mind) have done little to reassure a skeptical public about the merits of physical evidence. Police, prosecutors, courts and juries must be confident in the accuracy of laboratories and the trustworthiness of government witnesses. That’s hard to do when labs and experts are captive parts of the law enforcement establishment. Regaining confidence in forensics calls for a national system of independent, government-funded laboratories, much like the National Institutes, that are operated and controlled by top-notch scientists. Anything less is not good enough. Did you enjoy this post? Be sure to explore the homepage and topical index! Junk science links US DOJ/OIG report on Brandon Mayfield Home Top Permalink Print Share this post Posted 11/27/06 Pop psychology can lead investigators astray By Julius (Jay) Wachtel. “That really ordinary guy living next door could be a serial killer.” Dave Shiflett of the Bloomberg News says that’s the lesson we can draw from “Inside the Mind of BTK,” John Douglas’s new book about the infamous serial killer Dennis Rader, who tortured and murdered ten Wichita women between 1973 and 1991. But, wait! John Douglas is the most famous FBI profiler ever, an author of several true-crime best sellers and the model for Jodie Foster’s superior in “Silence of the Lambs”. If a sick puppy like BTK can seem so “ordinary”, how could he be identified through profiling? That, according to a lengthy exposé in The New Yorker (“Dangerous Minds,” 11/12/07), is the problem. John Douglas and his FBI colleagues told Wichita police that BTK was an American male with a decent IQ, that he drove a decent car, liked to masturbate, was selfish in bed, a loner (but could get along socially), uncomfortable with women (but could have women as friends,) maybe married, maybe not (but if married his wife was younger or older,) and so forth. Thankfully, officers managed to eventually solve the case sans profile. Rader was nothing like the FBI suggested. He was married, with children, active in his church and a pillar of the community. Profiling is one of several psychological techniques, along with investigative hypnosis and the recovery of repressed memories, that gained popularity during the free-wheeling 80’s. Although the latter methods have been thrashed for over-promising, under-performing and generally leading investigators astray, profiling lives on, its findings so elastic that they can seldom be disproven. It’s when profilers get specific that the nonsense becomes obvious. On the morning of January 21, 1998, Stephanie Crowe, 12, was stabbed to death in her Escondido (Calif.) home while the family slept. Detectives soon zeroed in on her reticent 14-year old brother, Michael. After relentless interrogation, he confessed and implicated two friends. Both got raked over the coals; one confessed while the other didn’t. Police arrested all three. They and prosecutors remained confident in the case even after the coerced statements were suppressed. After all, didn’t the FBI profile conclude that the murder was planned? Didn’t profilers say that the killer had “familiarity, comfort and knowledge” of the residence and the victim’s bedroom? Months later, while the boys awaited trial, a violent, mentally ill transient whom detectives originally discounted as a suspect (in part because of the FBI profile) was arrested when DNA testing revealed that those spots on his clothes were the victim’s blood. Charges against the boys were dropped and the man was convicted and imprisoned. On November 5, 2003 Gary Ridgway, the “Green River Killer,” pled guilty to murdering 48 women in KingCounty between 1982 and 1998. The investigation dragged on for twenty years and several FBI profiles, the first prepared by -- you guessed it -- the celebrated John Douglas. Their conclusions: the killer was likely an unemployed transient who had left the area and was either dead or in prison. Fortunately, the cops had Ridgway in mind all along. Deputies knew that the married truck driver, a local resident, had a reputation for picking up prostitutes and playing rough. In 2001 new DNA techniques matched Ridgway to four of the victims. He got life without parole. During the 1996 Atlanta Olympics a bomb exploded in a city park, leaving two dead and more than one-hundred injured. FBI agents immediately focused on Richard Jewell, the security guard who found the device before it detonated and sounded the alarm, undoubtedly saving many. But the FBI didn’t see him as a hero. Convinced that the chubby bachelor who lived with his mother fit the profile of a lone bomber, the Feds searched his home and conducted an exhaustive, highly public investigation. Jewell was cleared after two months. But the stain on his reputation never disappeared. In 2003 police finally caught up with the man responsible. Eric Rudolph had used identical devices to bomb the park and a string of abortion clinics. He confessed and got life without parole. It’s the patina of science that makes profiling so disturbing, lending confidence in conclusions with no more factual basis than the prognostications of a horoscope. Although recent studies seriously challenge the technique’s reliability, the FBI’s thirty-odd profilers remain on the job, reportedly fielding more than one-thousand requests from local police each year. More than twenty years after its inception profiling chugs on, the embarrassing detritus of a decade when overburdened police and prosecutors were seduced by the promises of pop psychology. Let’s hope it doesn’t take us another twenty to rediscover that it’s shoe leather, not magic, that solves crime. Did you enjoy this post? Be sure to explore the homepage and topical index! UPDATES 07/21/10 An FBI profiler concluded that the murders of two mother-daughter pairs in 2009 were unrelated. With the suspected serial killer now in custody police are convinced the FBI was wrong. 04/28/10 Frank Sterling was convicted of murder in 1982 thanks to a confession extracted under duress and with the use of hypnosis. He was freed today after DNA proved that the original suspect, who went to prison for killing a child two years later, was guilty. NY wrongful convictions Report 04/26/09 Columbine author says that the killers weren’t loners or “socially inept” and that there is no profile for a school shooter 07/07/08 FBI admits there’s no such thing as a serial killer “profile”: News release Study Home Top Permalink Print Share this post Posted 11/20/07 POLYGRAPH: SCIENCE OR SORCERY? Its usefulness is mostly as a prop By Julius (Jay) Wachtel. Exposing a stunning breach of national security, Nada Prouty, 37, a former FBI and CIA agent, pled guilty this month in D.C. Federal court to nationalization fraud, illegal computer access and conspiracy. Admitted in 1989 on a student visa, the Lebanese immigrant staged a sham marriage and gained permanent residency. In 1997, now-citizen Prouty was hired by the FBI and allegedly started passing top-secret information about Hezbollah to accomplices. A few years later the super-achiever landed in the CIA, an even better place from where to compromise American secrets. So what’s the rub? Prouty sailed through FBI and CIA pre-employment polygraph exams, supposedly the toughest in the universe. In all likelihood she would still be a mole except that her name came up during an investigation of her brother-in-law, Talal Chahine, who allegedly channeled millions of dollars to Lebanese militants. The history of lie detection is replete with disasters. None seems worse than the case of Aldrich Ames, a CIA agent who got rich by exposing his colleagues to the USSR (Ames’ treachery led to the execution of several Soviet citizens who were spying for the U.S.) While pocketing bundles of cash Ames passed two routine CIA polygraphs, and when caught bragged that he had never employed countermeasures. Ames wasn’t lying. In an exhaustive 2001 report, the National Academy of Sciences concluded that the polygraph is worthless for screening job applicants and employees. It held out a bit more hope when polygraphs are used for investigating specific, known events (i.e., crimes), but cautioned that research that supports this more limited application lacks scientific validity and probably overstates the technique’s accuracy. That’s a warning to take to heart. Between 1982 and 1998 forty-two women, mostly prostitutes, were murdered in King County, Washington. Most of their bodies were found in or near the Green River. Suspicion soon fell on Gary Ridgway, a truck painter whom prostitutes accused of rough treatment. Ridgway took and passed a police polygraph. In 2001, improved DNA techniques proved that he was indeed the killer. Ridgway was arrested and plea-bargained to life without parole. Polygraphs are frequently used to narrow the field of suspects. They are routinely administered to the parents and caregivers of missing and abducted children. Results are not reassuring. In the 1997 disappearance of Sabrina Aisenberg, local police, who suspected the parents, called polygraph results “inconclusive,” while an ex-FBI polygrapher hired by the defense insisted that it cleared them. A like controversy dogged the investigation of the 1996 murder of JonBenet Ramsey, where police rejected the findings of a renowned polygrapher who insisted that the victim’s mother and father were being truthful. (The Ramseys refused to be tested by the FBI because its profilers told police that the murder was probably an inside job.) Leery of being led down the wrong path, many savvy investigators shun the polygraph as a “truth machine” but use it as a prop when physical evidence or witnesses are lacking. Refusing to take a polygraph can land one on the short list of suspects. Even better, a few guilty persons get so intimidated by the black box that they shrivel up and confess even before the test begins. It’s a form of legalized coercion that leaves no bruises and may be impossible to challenge in court. It’s no surprise that shortcuts to finding the truth are hugely popular. As long as we’re willing to dig in our pockets there will always be someone happy to supply all the elixirs we want. We will soon be reporting on other questionable techniques, including cognitive interviews, profiling, investigative hypnosis and the recovery of repressed memories. Stay tuned! Did you enjoy this post? Be sure to explore the homepage and topical index! UPDATES 04/28/10 Frank Sterling was convicted of murder in 1982 thanks to a confession extracted under duress and with the use of hypnosis. He was freed today after DNA proved that the original suspect, who went to prison for killing a child two years later, was guilty. NY wrongful convictions Report |
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The latter group includes two incidents with three or more fatalities, the shooting deaths of 
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removing the flash suppressor and limiting magazine capacity to ten rounds. Naturally, Sporters continued to chamber the same ammunition – the 
What is DNA?
These “short tandem repeats,” or STR’s, can take various forms.
allele may sometimes be undetectable because one contributor’s DNA is in a low concentration and a few alleles have “dropped out.” Other times an allele may be obscured by someone else’s peak. When two people touch an object, one profile might dominate while the other may be completely absent. These difficulties and differences in protocols can lead labs to vary a billion-fold when estimating mixed-sample match probabilities from the same data.
