CIA, FBI relying heavily on unreliable polygraph

While CIA denies McCarthy fired based on her polygraphs, critics say agencies use the tests as an excuse for fishing expeditions against employees.
Written by ZDNet UK, Contributor

In the age of retina scans and other biometric technology, it seems a bit anachronistic that the FBI and CIA are increasingly relying on the ancient polygraph test as an investigatory tool, but indeed they are, the Washington Post reports. And this even though there's a growing body of evidence that the test is profoundly unreliable. Because it measures physiological responses to stress, the test reports many false positives while letting the cooler operators slip through.

In settings in which large numbers of employees are screened to determine whether they are spies, the polygraph produces results that are extremely problematic, according to a comprehensive 2002 review by a federal panel of distinguished scientists. The study found that if polygraphs were administered to a group of 10,000 people that included 10 spies, nearly 1,600 innocent people would fail the test -- and two of the spies would pass.

Now a question is being raised as to whether Mary McCarthy, the CIA officer who was fired for allegedly leaking information about the agency's secret European prisons to the Post, was fingered based on her polygraph tests.

CIA officials have said that McCarthy failed more than one polygraph examination administered by the CIA, but the details surrounding those interviews remain unclear. Dozens of senior-level CIA officials have been subjected to polygraph tests as part of the inquiry, which is aimed at identifying employees who may have talked to reporters about classified programs, including providing information about the agency's network of secret prisons for terrorism suspects.

A CIA spokesman said McCarthy's firing was the result of a wide-ranging investigation, not solely on her failed polygraphs. In any case, the Post says, the real power is not in the accuracy of the tests but in the fear it creates.

"In each and every test, what happens is after question two or three the questioner will pause and very deliberately take a long hard look at the chart and take a deep breath and sigh and say, 'You did really well on question one, but on the second question, about whether you released classified information, I am getting a strange reading. Tell you what -- I am going to turn the machine off and I am going to ask whether there is something you want to get off your chest.' "

"That is what the polygraph is about," said [Alan Zelicoff, a former scientist at Sandia National Laboratories who quit because he believed that polygraphs are unethical], who has testimony from several employees who are angry about the tests. "It is about an excuse to conduct a wide-ranging inquisition."

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