The announcement that Anita Faye Hill had taken and passed a lie detector test on her allegations of sexual harassment against Supreme Court nominee Clarence Thomas caused an uproar Sunday on the Senate Judiciary Committee, but experts were quick to point out that while the polygraph is considered a valuable investigative tool its accuracy can vary widely.
Lie detector tests are not admissible as evidence in federal courts or in many state proceedings, and the ultimate impact of Hill taking such a test in the bitter fight over Thomas' confirmation remains to be determined.
Sen. Patrick J. Leahy (D-Vt.), a committee member, predicted that Hill's lie detector test would prove significant. "It may not be admissible in a court of law, but it is certainly going to weigh heavily on the minds of a lot of senators," he said.
Thomas' Republican supporters, on the other hand, denounced what they characterized as a dubious political trick. And they moved immediately to prevent it from becoming a factor in the ongoing committee hearings.
"You can find a polygraph operator to do anything you want him to do, just like you can find a pollster," declared Sen. Orrin G. Hatch (R-Utah), one of Thomas' most ardent supporters. "To throw that into the middle of a Supreme Court nomination as though it's real, legitimate evidence is highly offensive . . . exactly what a two-bit slick lawyer would try to do."
Committee Chairman Joseph R. Biden Jr. (D-Del.) agreed and overruled one of his fellow Democrats, Thomas critic Howard M. Metzenbaum of Ohio, when he tried to get a reference to the polygraph test entered into the hearing record.
"If we get to the point in this country where lie detector tests are the basis upon which we make judgments . . . we have reached a sad day for the civil liberties of this country," Biden said.
Since the charges essentially come down to Thomas' word against Hill's, with no direct evidence brought forward thus far to resolve the conflict, the issue of her credibility has become paramount.
President Bush said earlier in the day that it would be "a stupid idea" for both Thomas and Hill to take lie detector tests to help determine which one was telling the truth about the sexual harassment that Hill alleges Thomas inflicted on her when she served as his aide at the Education Department and the Equal Employment Opportunity Commission in the 1980s.
"If the idea is challenging the word of one over another, to use the lie detector test in that way, I reject it," Bush said.
Although Leahy called the test results a "very significant development," several polygraph experts noted that the accuracy of the test depends on the expertise of the person administering it. And two polygraph experts challenged the competency of the examiner who tested Hill.
Paul K. Minor, a private security consultant who for nine years headed the polygraph division at the FBI, administered the test at the request of Hill's attorneys. He asked the University of Oklahoma law professor if she had fabricated her allegations that Thomas sexually harassed her by repeatedly asking her for dates and by discussing his sexual prowess with her in explicit and often vulgar terms.
"She answered no. There was no indication of deception to any of the relevant questions," Minor told reporters outside the hearing room where the committee was meeting. "It is therefore my opinion Ms. Hill is truthful."
While he is considered to be an expert in his field, Minor's reputation is not without controversy.
In July of 1980, Minor, who was then with the FBI, administered two polygraph tests to Herman Sillas, then the U.S. attorney in Sacramento, to determine the veracity of allegations that he had taken a $7,500 bribe from a prison inmate several years earlier. Sillas resigned after failing both polygraph tests.
At the request of Sillas' attorneys, the results were later examined by other experts who concluded that the tests had been improperly administered and the results "seriously flawed," according to Dr. Chris Gugas, chairman of the National Polygraph Assn.
Another expert, Lynn Marcy, who was then president of the American Polygraph Assn., was called in to administer the test for a third time and the results of that test indicated that Sillas was telling the truth.
"We filed complaints against Minor with the FBI and asked the American Polygraph Assn. to investigate him," said Richard Hickman, a San Francisco-based polygraph expert who, along with Gugas, reviewed the results of Minor's test.
Hickman said the way in which Minor phrased the questions he put to Sillas, along with what he remembers as being "serious" shortcomings in the methodology Minor used, raised doubts about his competence at the time.
A spokesman for the FBI, however, said that Minor had retired from the bureau in 1987 with his record there unblemished.
Minor could not be reached for comment Sunday. A man answering the telephone at his Northern Virginia residence said he left Washington immediately after announcing the results of Hill's test and was en route to New York City.
However, a member of Hill's legal team, Harvard University law professor Charles Ogletree, said Minor was chosen to administer the test because of his reputation as one the foremost polygraph experts in the nation.
Speaking to reporters earlier in the day, Minor said he put four key questions to Hill, asking if she had lied in her testimony or had fabricated the sexually explicit remarks she attributed to Thomas, who has categorically denied making them.
The questions Minor put to Hill were:
--"Have you deliberately lied to me about Clarence Thomas?
--"Are you fabricating the allegation that Clarence Thomas discussed pornographic material with you?
--"Are you lying to me about the various topics that Clarence Thomas mentioned to you regarding specific sexual acts?
--"Are you lying to me about Clarence Thomas making references to you about the size of his penis?"
Hickman said it was impossible to tell from the wording of the questions alone whether he or other experts would agree that the test had been administered properly. "We'd have to look at his charts, at his technical work and the control questions he asked to evaluate the test procedure," Hickman said.
Normally the procedure involves a lengthy interview in which the examiner also asks a series of irrelevant questions to determine the person's "base line response" to the test, which uses electrodes and other devices to measure certain "arousal" reactions.
Once that is established, cardiovascular activity and breathing rates are measures for signs of stress that may indicate a person is lying.
One key factor in determining the accuracy of the test is the length of the questions asked, Hickman said. The questions have to be "as short as possible to ensure that the person answering the question does not start to react before you've finished asking it."
While not admissible as evidence in federal courts, lie detector tests are widely used by the FBI, CIA and other branches of the government.
Ogletree said Hill wanted to take the test to counter the attacks on her credibility by Republican senators defending Thomas. "She wanted to face the issue, she would live by the results," he said.
Given the ongoing controversy over the accuracy of polygraph tests, it is not likely that this one--even if it has been administered properly--can be relied upon to establish a truth that has eluded the members of the committee over several days of agonizingly explicit and emotionally powerful testimony.
But the fact that Hill volunteered to take the test may in the end carry more weight than the answers themselves, Leahy said.