Here is direct commentary from Friday’s Texas Forensic Commission’s DNA focus group on what to do with adjusting ( i.e. dialing it back from over its optimistic past) DNA mixture analysis. Below, Grits describes the quandary of DNA being this forensic declared “gold standard” of being modified to a lesser plateau of certainty. Two opposing outcomes seem to be apparent: 1) this could be repeated in every state of the Union and 2) consensus of what to do needs to be determined at the national level with mandatory rules of the road.
I think most people are ignoring statements that this adjustment “won’t exclude the perpetrator” as it ignores the seminal TX case, using the proposed adjustment, had the probability of a “mis-match” likelihood ratio going from one in a million to 1 in 38.
This may require a ground breaking entry by the Congress or the Executive Branch to avoid the mish-mash guaranteed by outcome 1). Unfortunately, in the forensic science community/legal interface, the mechanism for this type of reform/science advance has always been state-by-state. Unless its the feds declaring changes in their internal methods as seen in their decommissioning hair comparisons, bullet lead profiling, and many years ago, handwriting comparisons.
Here’s a excerpt from Grits:
“Yesterday for work I attended a Forensic Science Commission committee meeting in Dallas on DNA mixtures where the agenda had suggested they’d be parsing prosecutor disclosure obligations and mapping out a path toward reviewing old cases. Instead, the committee couldn’t field a quorum, so four scientists brought in to advise them were left to field a lengthy panel-discussion/Q&A which clarified some issues and on others, only emphasized how muddy much of this remains.
Terri Langford at the Texas Tribune was the only reporter there, here’s her story. In general, she correctly summarized:
experts tried to temper the expectations about DNA testing that were built over more than a decade.
“One of the problems was DNA was called the gold standard,” Bruce Budowle, director of the University of Texas Health Science Center’s Institute of Applied Genetics, said. “Big mistake.”