Scientists found problematic forensic methods used to convict Steven Avery
04.12.16 By Innocence Staff
In a recent op-ed in the Pittsburg Post-Gazette, four experts participating in a forensic science research program highlight the problematic forensic science used to convict Steven Avery for the 2005 murder of Teresa Halbach.
Experts Lucas Mentch, Maria Cuellar, William C. Thompson and Clifford Spiegelman are in the midst of a year-long evaluation of forensics sponsored by the Statistical and Applied Mathematical Sciences Institute. While watching “Making a Murderer,” the popular Netflix series about Avery’s case, the experts found many striking examples of the inadequately validated forensic methods they have been studying.
The most glaring example, according to the experts, was the question of whether blood stains in Halbach’s car allegedly left by Avery contained a chemical preservative known as EDTA, which is used in crime labs to preserve blood samples. During Avery’s trial, his defense team alleged that law enforcement took a sample of Avery’s blood from a crime lab and smeared it on the dashboard of Halbach’s car in order to frame him for the crime.
Hoping to dispute this claim, the prosecution requested that the FBI develop a test to detect EDTA in dried blood. After hastily developing and performing a test on only three of the six stains found in the car, an FBI chemist testified that the test failed to detect EDTA. Based on this, he concluded that EDTA was not present in any of the six stains. The prosecution then used the absence of EDTA in the samples tested as further evidence of Avery’s guilt.
The researchers raised concerns about developing a test in a short period of time for the purposes of a trial and the provision of conclusions on untested evidence. The op-ed also discusses the problems of contextual bias that might have influenced the DNA testing in the case.
Read more about the problematic forensic methods used in Steven Avery’s prosecution.
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April 24, 2016 at 8:24 pm
4th paragraph, 3rd line
the word “ETDA” should be “EDTA”
Charles Robbins May 19, 2018 at 4:40 am
There was already a reliable test for edta in blood which was used during the Simpson trial.
My question is this: why was there a need for the FBI to develop a new test in this case?
One would have to wonder why the old test was not requested to be used by the defense team. Why is the FBI involved in this case at all? Once again, the FBI laboratory is involved in questionable activities.
Remember this; whatever has happened to Mr. Avery could also happen to any one of us.
If law enforcement sets out to “get even” with someone, they can, and will, make sure that evidence to convict you will be available… whether that evidence is real or manufactured? That is the question you must answer for yourself.