You read THIS then:
Tainting Evidence : Inside The Scandals At The Fbi Crime Lab
http://www.amazon.com/exec/obidos/tg/detail/-/0743236416/104-4072512-0747166?v=glanceBut if scientific crime-fighting is fallible and flawed, those problems rarely come to light. One exception was in July 1994, when U.S. Today and the Gannett News Service published a survey. Believing that the claim that the bloody glove found on O. J. Simpson's estate had been planted was far-fetched, the newspaper trawled legal and media databases for comparative cases. They found 85 instances since 1974 in which prosecutors had knowingly or unknowingly used tainted evidence that had convicted the innocent or freed the guilty. In the same period, 48 people sentenced to death were freed after convictions were found to be based on fabricated evidence or because exonerating or exculpatory evidence was withheld.
These were just the known cases, cases that for one reason or another had come to light or made the news. "In the United States we take science as gospel," said Ray Taylor, a San Antonio-based lawyer and forensic pathology expert, commenting on the survey. "The public perception is that faking science is rare. The truth is it happens all the time."
<snip>
As the FBI’s research and training facility came to dominate forensic science research in this country during the 1980s, the laboratory division continued to employee and promote researchers and examiners who patently ignored the most basic scientific procedures and fixed results. As its own staff patently ignored ASCLD guidelines on documentation, record retention and report writing, the FBI lab would exhort others to follow the guidelines in the pages of its periodical, Crime Lab Digest. Thousands of personnel from other crime labs would be trained by an institution that failed to train or supervise its own staff. Hundreds of crime lab managers from around the country would be trained by an FBI laboratory division run by managers who failed to check examiners' work, ignored repeated complaints about sloppy or negligent work, and even promoted some of the worst offenders.
It was a scandal that kept on growing, affecting hundreds, maybe thousands of lives. A scandal of atrocious forensic science that not only threatened to punish the innocent but to free the guilty. A scandal that demonstrated that J. Edgar Hoover lived on, that the FBI lab was unaccountable even to the rest of the FBI, let alone to Congress, the scientific community or the general public. It was a scandal that when it finally broke would be all the more devastating as result of years of pretence, denial and face-saving, years of putting image before reality.
http://crimemagazine.com/tainting_evidence.htmThe FBI lab's woes came to light in the mid-1990s after FBI chemist Frederic Whitehurst went public with allegations of wrongdoing and shoddy work inside the lab.
The department's inspector general conducted an 18-month internal investigation that concluded that 13 lab technicians had performed flawed scientific analysis or provided inaccurate, pro-prosecution testimony in cases, including the 1995 Oklahoma City bombing and the 1993 World Trade Center terror attack.
http://www.concordmonitor.com/stories/front2003/031703fbifallout_2003.shtmlDespite the FBI's changes at the lab, the AP reported recently that one technician has since mistested more than 100 DNA samples and another of its expert witnesses has been charged with knowingly giving false testimony.
http://www.philly.com/mld/philly/news/nation/5954038.htm