The Innocence Project discusses forensic science in our judicial system.

A symposium at the ACS meeting illuminates challenges for and rifts in the justice system:

The Innocence Project is a nationwide legal network that works to exonerate innocent prisoners through DNA testing. Experts agree that the Innocence Project has changed the justice system for the better, both by freeing the innocent and by encouraging scrutiny of all types of evidence presented in the courtroom.

It is perhaps the most visible player in a movement that is challenging improper use of forensic science in the legal system. That role has led to tensions with some members of the forensic science community, who are concerned that the criticism of crime labs that has emerged is unfairly broad. In an effort to spark a dialogue with chemists and rally them to the cause, the Innocence Project held a symposium at last month’s American Chemical Society national meeting in Philadelphia. The session highlighted challenges in forensic science as well as forensic techniques that lack scientific vetting.
Before the Innocence Project existed, says Peter M. Marone, director of the Virginia Department of Forensic Science, “was the little guy getting a fair shake? No.” The organization’s efforts to free its mostly destitute clients date to 1992, when attorneys Peter J. Neufeld and Barry C. Scheck, both members of O. J. Simpson’s defense team, established the Innocence Project as part of Yeshiva University’s Benjamin N. Cardozo School of Law. Since its founding, the Innocence Project has had a hand in nearly 300 exonerations.
It was DNA that made the Innocence Project possible, says chemist Jay A. Siegel, a longtime forensic scientist and adjunct professor at Indiana University-Purdue University Indianapolis. The technology matured in the academic community, and if used properly, makes it possible to link an individual to evidence such as bloody knives or semen-stained clothing. The absence of DNA doesn’t always mean a person is innocent, so DNA alone isn’t enough to solve a crime, Siegel cautions. “That’s a myth perpetuated by ‘CSI,’ ” the popular TV show.
What’s more, some types of DNA technology have shortcomings, as Boise State University geneticist Greg Hampikian cautioned Philadelphia meeting attendees. Sample collection methods haven’t changed since DNA’s courtroom debut in the 1980s, even though assay sensitivity has increased dramatically, he said. His group has shown that detectable amounts of DNA can transfer between specimens if a handler forgets to change gloves. Hampikian, director of an Innocence Project affiliate in Idaho, also showed that if exposed to extraneous details about a case, experts can give very different interpretations when analyzing DNA mixtures, as can appear in cases of gang rape (Sci. Justice, DOI: 10.1016/j.scijus.2011.08.004). Despite these caveats, DNA testing is the gold standard among forensic disciplines, because it has undergone thorough scientific vetting.
Other forensic tests lag behind DNA in several ways. These tests include fingerprinting, as well as the hair, soil, and denim imprint analysis used in Barnes’s trial, and the bite-mark analysis from Krone’s trial. They cannot point to an individual, and little to no research has been conducted toward standardizing them or defining their error rates. Problems arise when attorneys, judges, or juries attach the same aura of reliability to all forensic sciences regardless of their scientific merit, says attorney Josh D. Lee, cochair of the Forensic Science section of ACS’s Division of Chemistry & the Law and coorganizer of the Philadelphia session.
To John J. Lentini, arson investigation is a particularly troubling example. Much of the field has been “witchcraft that passes for science,” he said in Philadelphia. Lentini, a fire investigator, discussed the 1980 “Fire Investigation Handbook,” which codified unwarranted generalizations. It was published by the National Bureau of Standards, the agency that predated the National Institute of Standards & Technology. The book associated irregular cracks in glass—called crazed glass—with rapid heating, which suggests the use of fire accelerants. It also stated that narrow V-shaped char patterns on walls indicate fast-developing, hot fires. These myths, as Lentini called them, were once considered scientific fact in courtrooms. As an example, Lentini said, they were cited in the case of Cameron Todd Willingham, a Texas man executed in 2004 for setting an arson fire that almost certainly wasn’t arson.
V-shaped patterns, as research from Lentini and others shows, can occur in fires set accidentally, not just arson fires. Crazed glass actually forms during rapid cooling, such as when fires are put out, not during rapid heating. The National Fire Protection Association has published scientific-based guidelines for arson investigations since 1992. But Lentini cautioned that misperceptions still abound.

Traditional forensic science got grandfathered into the justice system, says Carrie Leonetti, an attorney who has served on the American Bar Association’s Task Force on Biological Evidence. “It’s a lot harder to ask a court to exclude evidence that has been admitted for a hundred years than to exclude evidence it’s never seen before,” Leonetti, of the University of Oregon School of Law, explains. “Because DNA was so new, it went through incredible vetting.” That didn’t happen for other forensic disciplines, she adds.

Research conducted by the Innocence Project suggests that the number one contributor to wrongful convictions is eyewitness misidentification. But number two, involved 45% of the time, is faulty forensics, which the Innocence Project defines as testimony that isn’t scientifically vetted, exaggerated testimony, and forensic misconduct.

Nor is exaggeration or falsification of forensic testimony commonplace, adds Philadelphia Department Police Forensic Services Bureau chemist David J. Wolf. “We don’t say whatever we feel like in court,” he says. “We have mock trials within our laboratory to teach new chemists how to go about testifying. It takes years to learn how to testify really well.”http://cen.acs.org/articles/90/i37/Forensic-Science-Innocence-Project.html

The Innocence Project: Science helping (video).

An unusual symposium showcasing chemistry’s role in righting some of the highest-profile cases of innocent people proven guilty unfolds today at the 244th National Meeting & Exposition of the American Chemical Society (ACS), the world’s largest scientific society. It features presentations by forensic scientists, attorneys and others who used science to right wrongs, freeing innocent people and saving the lives of prisoners on death row. http://www.ustream.tv/recorded/24848172