Convoluted Brian

the weBlog of Brian McCorkle

The Importance of Understanding

Lie Detectors and other Investigator Fallacies

Green Bay, Wisconsin television station WGBA, had a segment called Truth About Lying on the ten o’clock news of 4 February, 2008. The local news media often act as a conduit for PR from the law enforcement agencies. If the police want to undermine an accused with true or false information, the news teams are happy to regurgitate what they are fed.

This segment was used to showcase Marinette County Sheriff’s Department Detective Anthony O’Neill’s expertise in lie detection. O’Neill was singing the praises of the polygraph. Truth (or lie) detection is something that has been pursued by intelligence agency and law enforcement for a long time. No one is there yet, contrary to claims from the polygraph vendors.

O’Neill was one of the first to interview the Avery’s in Crivitz Wisconsin and interrogated Brendan Dassey in a police care in November, 2006. He attempted to intimidate and bully Brendan Dassey into naming Avery as the murderer of Teresa Halbach.

He also testified at the Brendan Dassey trial that he didn’t keep notes of Dassey’s demeanor, but that since Dassey didn’t maintain eye contact that meant that Dassey was guilty. O’Neill claimed that his years of experience were sufficient to prove his claim. Dassey’s attorneys did not challenge this absurd testimony.

In the real world, doctors with more experience (and training) than O’Neill will engage in things like differential diagnosis before condemning their patient to any kind of guilt. Poor eye contact is symptomatic of a multitude of conditions. These include being the subject of intimidation and being in a threatening situation. O’Neill was definitely belligerent and threatening when he had sixteen‑year‑old Dassey trapped in a squad car. It’s too bad that psychologists and psychiatrists don’t speak out against this voodoo medicine that Detective Tony O’Neill and other like him purport to practice.

There is a big problem with O’Neill, and other police personnel, administering lie detector tests to suspects. He is biased. He can claim that he is not, but institutional bias is a fact of life. That is why double‑blind tests are the rule in medical test trials. O’Neill both administers and evaluates the test when he performs the testing. Chances are he already has determined guilt or innocence or someone had directed him to a sense of guilt. That will bias the examination even if the technology were valid.

In a 1986 feature done by 60 Minutes, three expert polygraph examiners each fingered the wrong person with “100% accuracy.” A claim of a stolen camera was the purpose of the test. There was a bias to the test, however. The person requesting the polygraph indicated which subject they felt was guilty and the examiner somehow picked that one. This is the kind of bias and error that ruins people lives.

In 1985, Russell Dann was stabbed by his estranged wife Laurie with an ice pick that narrowly missed killing him. The investigating offices prejudged the situation claiming that the wound was self‑inflicted and then botched evidence collection. Both Danns were both given polygraph examinations. Laurie passed hers. Russell failed without even taking it. In 1988, Laurie Wasserman Dann entered an elementary school, shot and killed a second grade boy, wounded several others, and severely wounded a man before suiciding.

O’Neill also spoke of his evidence that both Steven Avery and Brendan Dassey were lying about their involvement in the Teresa Halbach disappearance. He claimed because Avery offered a reason why he didn’t do the crime that was evidence of a lie, since the innocent don’t protest. Yet, I see people giving real world alibis that are corroborated. But, according to O’Neill those people must be guilty. Of course, if the suspected said nothing that would also be red flag also if the detective desired.

The behavior the Manitowoc County deputies accused of planting evidence would make them liars also by this standard. They offered reasons why they didn’t plant the key that operated Teresa Halbach’s RAV4 found in Avery’s bedroom. But, the bedroom had been thoroughly search several times before the key appeared in plain sight. There were three deputies present when it was found. One of them planted the key. One of them claimed under oath that aliens put the key in home.

O’Neill’s claim about Dassey was about his demeanor. This detective turned amateur psychologist has no doubt that Dassey was lying because of visible discomfort. Of course, sitting on an undersized sofa that was uncomfortable would have no effect if we believe O’Neill. Nor would the fact that Dassey had recently undergone at least two prior interrogations be important by his criteria.

WGBA showed a film clip of Dassey in the substandard Manitowoc County interrogation room. A clip from the earlier session at the Two Rivers Police Depart did not show all the signs that O’Neill claimed simply because the layout was much better and neutral, but the news team did not show that. The Manitowoc County interrogation room is very poor. Only one of the interrogators was visible (most of the time) and the seating for the subject was designed to be uncomfortable. That will cause distress.

The WGBA commentator stated that O’Neill offered a lie detector test to Steven Avery, but Avery declined it as if that meant something incriminating.

I would also decline the test. There is built‑in bias. Police polygraph examiners have a bias to incriminate those believed to be guilty rather than perform an unbiased examination. And the results are never that reliable anyway. If a person is nervous about an event not related to the investigation that will show up. One man was convicted of murder and later exonerated. He was terrified that a marital infidelity would show up during the examination.

We all want to get the bad guys. It is important that we don’t lock up a bunch of the innocent as collateral damage. The US Customs was told to stop racial profiling for suspected smugglers. The result was profiling on behavior characteristics and that was more efficient than the racial profiling. But, the behavior is used to conduct searches rather than declare guilt. Guilt is determined by the evidence not some detective claiming to be omniscient.

It seems that someone is trying to make Dassey guilty because of some behaviors. But, the evidence that was claimed to incriminate Dassey was actually statements that were fed to Dassey first. And, he did a poor job of repeating the statements back to the interrogators.

But, the kind of hocus‑pocus that Tony O’Neill claims is valid is guaranteed to cause false imprisonments. I am certain that O’Neill believes what he claims and that makes things worse. Such an attitude prevents good solid investigation and increases the chances for error. In 1996 Richard Jewel discovered a bomb at the Olympic Park and acted to save many people. With another bogus technique called profiling, the FBI decided that Jewel had planted the bomb and then wasted time and resources while the real bomber went on his way. The damage done to Jewel because of this malarky was never undone.

I’m not sure what the purpose of the so‑called Truth About Lying was. But, it was superficial coverage as usual. I wonder if this was a public relations ploy to continue claims of the guilt of Dassey and Avery. Given that the confessions of Dassey are very dubious, is this an attempt to pretend that the Dassey interrogations were the result of good police work?

by Brian McCorkle
posted on 7 February, 2008 at 20:00 pm
in category Criminal Justice,Rants

The local WGBA news team aired a propaganda segment claiming a police polygraph examiner gets valid results. But, since the examiner administers and evaluates the examination, the result will be skewed. Not to mention, that police sometimes judge a person guilty prematurely and then institutional bias will kick in.

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