« Video of the Day | Main | The East, The West, and The Ivy League »
My interview with Radley Balko, who is meeting his fans in Denver tonight, began here. Part two is here. And part three is here. The next question:
Q. Perhaps the most significant story you've covered lately involved
prosecutors using the services of a bite mark expert, though evidence
suggests he is no expert at all. Can you briefly describe that case,
reflect more generally on the idea of expert witnesses in our criminal
justice system, and explain why you think the status quo is
problematic?
In the 1990s, a Mississippi dentist named Michael West became a popular expert witness
for prosecutors because he claimed to be a bite mark expert who could
find and identify tooth impressions in human skin that no other expert
could see. He was eventually exposed as a fraud by 60 Minutes
and other media outlets, though he continued to testify in Mississippi,
and there are still people in prison who were convicted primarily
because of his testimony.
West got on my radar as I've reported on the
problems with the forensics system--particularly in Mississippi, where
until last year, one doctor who colleagues say is sloppy and disreputable has done 80-90 percent of that state's criminal autopsies for the last 20 years.
That doctor, Steven Hayne, and West were the primary reason two men
were convicted of the rape and murder of two little girls in the early
1990s in Mississippi. DNA testing exonerated both men last year. Earlier this year, I wrote about another case in which the two men may have fabricated bite mark evidence in a murder case, and another in which a defense attorney conducted an amusing sting to expose West's charlatanism.
Fraudulent experts like West and Hayne have been able to thrive
because of some pretty significant flaws in how forensic evidence is
used in the criminal justice system. The main problem is that it's
presented as science, but isn't really subject to the sort of rigorous
testing and peer review that other fields of science undergo. Bite mark
evidence, for example, should never be used in a court room. There's no
legitimate scientific literature to back up the idea that you can trace
tooth imprints on human skin to a single suspect. But the National
Academy of the Sciences warned in a big report
earlier this year that even areas of forensics we once thought
infallible, such as fingerprint evidence, are subject to error, whether
it be malicious misconduct, or less nefarious bias and innocent
mistakes. The certainty of DNA testing has exposed the flaws in how
we've traditionally dealth with forensic evidence.
Juries tend to put a great deal of faith in witnesses that judges
certify as experts. The problem is that judges haven't adequately
performed their duty as gatekeeper, both at keeping frauds out of the
courtroom and preventing legitimate experts from testifying beyond
their expertise or exaggerating the certainty of their conclusions.
Comments on this entry have been closed.