Humble Observer managing editor Martin L. de Vore reports on a talk given by Humble, Texas police polygrapher Kelly Hendricks. Excerpt:
Braving cloudy skies and a light misty rain, North Harris County Criminal Justice Association (NHCCJA) members who attended the organization’s April meeting got an inside look at the controversy surrounding the use of voice stress analysis (VSA) technology by police.
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Hendricks then spent the next 30 minutes of the meeting covering the VSA controversy and the pending legislation that would affect its use in the state of Texas. Hendricks said that VSA technology is not reliable and should be eschewed in favor of current polygraph technology.
“Voice Stress Analysis (VSA) is only right about 48 percent of the time,” Hendricks said. “That’s less than fifty-fifty. Thirty-two different reliability studies since 1982, that individually range from 90 percent to 100 percent in accuracy and reliability, indicate that polygraph is the way to go instead of VSA. When all those figures are combined, in reality, what the figures show is that there is less than a two percent possibility of error with polygraph use. Compare that to the accuracy figures on VSA and it proves that VSA is not reliable and that polygraph is. If VSA or CVSA worked, we’d be first in line to use it.”
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Hendricks also shared his views on the identical bills House Bill 817 (HB 817) and Senate Bill 1221 (SB 1221) that are currently being considered by the Texas Legislature.
HB 817 is a bill involving VSA that was filed on Jan. 22, 2001, by District 61 state Rep. Phil King of Weatherford. It was still pending in committee at the time of the NHCCJA meeting on April 3.
SB 1221 was filed on March 7, 2001, by District 15 state Sen. John Whitmire of Houston. At the Senate Committee on Criminal Justice’s hearing on April 4, it was also left pending in committee following testimony from both the bill’s advocates and from its opponents (including Hendricks, who testified against SB 1221 on behalf of the Humble Police Department).
HB 817 and its companion bill, SB 1221, relate to the use of a computerized voice stress analyzer by a licensed peace officer during a criminal investigation. Briefly, Hendricks listed some of the components of the proposed legislation:
A licensed peace officer who is a certified voice stress examiner is not required to be licensed under this chapter to use a computerized voice stress analyzer during a criminal investigation.
The certification to use a voice stress analyzer must be made by the company who manufactured the voice stress analyzer; or the governmental entity who appointed or employs the peace officer.
The act takes effect immediately if it receives a vote of two-thirds of all the members elected to each house, as provided by Section 39, Article III, Texas Constitution.
If the act does not receive the vote necessary for immediate effect, the act takes effect September 1, 2001.
Hendricks strongly opposes the bill and asked those in attendance to contact their state representatives and senators to voice their opposition to it.
Polygraphers are quick to point out the shortcomings of the competing pseudoscience of “Computerized Voice Stress Analysis” (CVSA). But polygraphy, like CVSA, has not been shown by peer-reviewed research to work at better than chance levels in the field. The “research” Hendricks invokes to support his claim that “there is less than a two percent possibility of error with polygraph use” appears either in non-peer-reviewed trade journals or, where published in peer-reviewed scientific journals, involves laboratory experiments with paid volunteers who committed “mock” crimes and had little or nothing to lose in the event of a false positive outcome: motivational conditions that do not apply to the field. Moreover, such studies purporting to support the high validity of polygraphy fail to take into consideration the effect of polygraph countermeasures (such as those discussed in Chapter 4 of The Lie Behind the Lie Detector).