This is going to put the cat among the pigeons. There have been several high profile cases in Australia where forensic evidence has been shown to be unreliable, and if the NAS is behind this report it is going to have a lot of impact in the US. Those guys are serious business.
Forensic science 'too unreliable', says reportForensic science is in crisis, with techniques like bloodstain pattern and bite-mark analysis routinely being used in convictions despite a dearth of evidence quantifying their reliability.
So says a report by the US National Academy of Sciences, which calls for the establishment of an independent federal body to raise standards, and new research to assess the reliability of many forensic methods.
In recent years, a number of high-profile exonerations have illustrated the pitfalls of placing too much trust in forensics and expert testimony. For example, last month Steven Barnes was released from jail after serving 20 years for the rape and murder of a high-school student in New York State in 1985.
Key to his conviction was expert testimony that soil on Barnes' truck tyres was similar to soil at the crime scene, and that an imprint on the outside of the truck matched the fabric pattern on the jeans worn by the victim when she was killed, but DNA evidence suggested he was innocent.
False convictionsOf particular concern is the use of comparative forensic methods like hair or fingerprint analysis to match a piece of evidence to a particular person, weapon, or place.
"With the exception of nuclear DNA analysis, no forensic method has been rigorously shown able to consistently, and with a high degree of certainty, demonstrate a connection between evidence and a specific individual or source," says the NAS report.
Despite its damning conclusions, many forensics scientists have welcomed the report. "I think it's long overdue," says Michael Baden, chief forensic pathologist for the New York State Police who has worked on a number of high-profile cases, including the deaths of Sid Vicious and John Belushi, and the trials of O J Simpson and Phil Spector.
"It brings criticisms of some of the reasons why so many innocent people get convicted in this country based on junk science," says Baden.
He cites the example of people have been jailed because a hair apparently matching the suspect has been found on the victim, but DNA analysis has cleared them at a later date. "Things that we've accepted as valid may not be valid," he says.
(Full article linked from headline)
Topic: Forensic science 'too unreliable', says report