"It profits me but little that a vigilant authority always protects the tranquillity of my pleasures and constantly averts all dangers from my path, without my care or concern, if this same authority is the absolute master of my liberty and my life."

--Alexis de Tocqueville, Democracy in America

Monday, April 2, 2012

Trayvon Martin Update - The Problem With "Experts"

The latest on the Trayvon Martin case -- which I predict will someday be a case study in journalism schools about "what not to do if you don't want to foment race riots" -- comes from the Orlando Sentinel, which apparently engaged two "audio experts" to analyze recordings of the screams on the 911 calls to determine whether it was George Zimmerman, the neighborhood watch captain, or Trayvon Martin, the victim of the shooting, who screamed for help:

Audio experts Tom Owen and Ed Primeau, who analyzed the recordings for the Orlando Sentinel using different techniques, said they don't believe it's Zimmerman who can be heard screaming in the background of the 911 calls.

"There's a huge chance that this is not Zimmerman's voice," said Primeau, a longtime audio engineer who is listed as an expert in recorded evidence by the American College of Forensic Examiners International. "As a matter of fact, after 28 years of doing this, I would put my reputation on the line and say this is not George Zimmerman screaming."

Owen, a forensic audio analyst who is also chairman emeritus of the American Board of Recorded Evidence, said he also does not believe the screams come from Zimmerman.
Software frequently used to analyze voices in legal cases shows a 48% likelihood that the voice is Zimmerman's. At least 60% is necessary to feel confident that two samples are from the same source, he said Monday on CNN. That means it's unlikely the screams came from Zimmerman, Owen said.
The experts, both of whom say they have testified in cases involving audio analysis, stressed they cannot say who was screaming. They have no samples of Martin's voice.

The last two sentences are the key.   The newspaper, if it was doing journalism and not simply advocating for Zimmerman's arrest (or, more likely, giving the newspaper-public what it wants, which is a sensational story that keeps on giving), would have filed this information after concluding that there was no news here.   The question at issue is:  who was screaming?   The so-called "experts" conclude that... "they cannot say."   We know it had to be Martin or Zimmerman.   They conclude that there is a chance that it isn't Zimmerman.   What do we know after reading this article that we didn't know before?  

Beyond that, as a lawyer I have to tell you that these kind of "experts" make me sick.   Any plaintiff's lawyer can find an "expert" who will say whatever they want him to say.  They will all have slick resumes with lots of nice-sounding credentials... they've been President of this association, or have won this or that award.   And they all are dying to get their names in the paper with word "expert" prominently highlighted -- that's how they make their living, after all, and being quoted in the newspaper is free advertising.   But then you cross-examine them and you find out that their methods are shoddy and their logic is full of holes and they didn't consider X, and they didn't think of Y.   And, oftentimes, you can use their own profession's published standards to eviscerate them on cross.

In this case, for instance, the "American Board of Recorded Evidence" publishes a standard for making comparisons of two recordings to determine whether they are made by the same person's voice.   Even the most casual review of this standard shows that, if the "experts" were applying their own profession's standard, the only conclusion they could draw would be that the recordings are "inconclusive."  

That being the case, what's the news?  

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