Tuesday, October 14, 2008
The fallibility of eyewitness testimony revealed by DNA exonerations in Dallas County and nationwide is not a relic of the past. Police and prosecutors still depend on the same discredited identification procedures to ensure convictions today.
Police use these techniques in a variety of crimes from murders to robberies. The difference between today's cases and the 19 exonerations involving sexual assaults is that often there is no DNA to ensure guilt or innocence.
"We've shown how unreliable eyewitness testimony is in sexual assault cases," said Rob Warden, executive director of the Center on Wrongful Convictions at Northwestern University law school. "But now the system itself is pretending that all of these armed robbery cases are just hunky dory when we know, if anything, it's no doubt less reliable in an armed robbery case than in a sexual assault case."
It's impossible to estimate how many wrongful convictions might be occurring in cases without genetic evidence, experts say.
"There is no question that there are many more mistakes that we will never know about because there is no DNA in those cases," said Edwin Colfax, an Austin researcher with the nonprofit reform group The Justice Project.
To examine whether the flawed practices highlighted by the DNA exoneration cases were still in use, The Dallas Morning News examined robbery trials in Dallas County from 2006 and 2007 – the last year of former District Attorney Bill Hill's tenure and the first year Craig Watkins was in office. Eyewitness testimony is the most crucial element in robbery cases.
The newspaper found that law enforcement still relies heavily on eyewitness testimony, even if corroborating evidence is weak and despite decades of research showing its shortcomings. [Mark Godsey]