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  • Background on United States v. Scheffer
  •   High Court to Rule on Trial Viability of Lie Detector Test Evidence

    By Joan Biskupic
    Washington Post Staff Writer
    Sunday, November 2, 1997; Page A15

    Robert Brisentine hooked his polygraph machine up to a murder suspect whose last best hope of getting the charges against him dropped was to pass a lie detector test.

    Working on a recent fall morning at a county jail on the Eastern seaboard, Brisentine strapped two rubber tubes across the man's chest, slipped a blood pressure cuff around his arm and fastened electrodes to his fingers, all to measure the man's physiological response to a series of questions. All to measure, ultimately, whether the man was a liar.

    The suspect was nervous, even panicky. At one point Brisentine suggested they take a break to let the man calm down. When they started again, the 40-year veteran polygraph examiner watched on his laptop computer as the machine recorded the peaks and valleys of respiration, blood pressure and electrical properties of the accused man's skin.

    Such scenes are repeated daily across the country and experts say the private business of testing criminal defendants is widespread and growing. Just last week, a lawyer for the young British nanny found guilty of murdering an infant tried to assert his client's innocence by saying she had passed a polygraph. Private companies use them to uncover employees who steal, prosecutors use them to extract confessions from criminals and the military uses them to safeguard national security. Last year alone, the Department of Defense ran 12,500 tests, in some cases using the results to elicit confessions of stolen classified documents or espionage.

    Where polygraphs aren't used, however, is inside an actual court room during trials. That could change. On Monday, the U.S. Supreme Court will address for the first time the validity of polygraph testing and consider whether automatic bans are unconstitutional.

    The precise question before the justices is whether rules that keep polygraph evidence out of court violate a defendant's Sixth Amendment right to present evidence in his favor. If the Supreme Court were to open the door to the use of polygraphs in court, it would immediately lend credibility to those who say the machines can accurately determine whether a person is lying by recording breathing that becomes shallow, blood pressure that rises and skin that moistens.

    Such a ruling could also transform the evidence each side puts before a jury. While the case to be heard by the high court deals only with a defendant's right to introduce polygraph testimony, a ruling supporting that notion would no doubt lead to a case testing whether prosecutors could use it against defendants.

    The idea that a machine and examiner can effectively get inside someone's head and determine truthfulness has evoked skepticism since the first polygraphs were developed in the early 1900s.

    While the Department of Defense labels the polygraph "one of our most effective investigative tools," congressional leaders who pushed through a 1988 law prohibiting private employers from forcing job applicants to submit to testing called the polygraph "witchcraft" and an "instrument of intimidation." Former Secretary of State George P. Schultz threatened to resign rather than take a polygraph examination when the Reagan administration instituted new security measures, calling the tests inaccurate and demeaning.

    But to veteran examiners like Brisentine, the small black polygraph box, now about the size of a paperback book, can be more accurate than many traditionally accepted types of evidence. If handwriting analysis can be put before a jury, some argue, shouldn't a polygraph test be too?

    "You don't fool the instrument. You fool the examiner," Brisentine, the former chief examiner for the Army, told a reporter in a demonstration after he had tested the murder suspect. "And I believe that if an examiner does it properly and doesn't have a preconceived idea [of the person's guilt or innocence of a crime], he will get the truth."

    Examiners ask three different kinds of questions to get a range of responses and points of comparison: some questions are neutral and non-threatening, perhaps about the weather or the color of the room; some work as "control" questions and often regard illegal behavior in the abstract, for example, "Before 1997, did you ever intentionally hurt anyone?" Finally, there are the pointed queries about the crime at issue: "Did you stab Joe Smith?"

    The case before the court involves a former U.S. airman who was court-martialed for using methamphetamines, passing bad checks and going AWOL. Yet he had passed a polygraph test asking whether he had used the illegal drugs.

    Advocates for the use of polygraph results at trial, including Air Force lawyers representing Edward G. Scheffer, point to various laboratory and field studies, contending the method accurately assesses deception about 90 percent of the time. The lower court ruling said a defendant has a right to at least try to lay the foundation for the reliability of polygraph results, just as he would a multitude of other scientific evidence.

    On the other side, however, the Justice Department insists there is no way to test if a polygraph is reliable. It notes that a person who was caught lying in one exam might not be detected in a second one.

    And the government, despite using polygraphs widely, says they are easy to beat by using "countermeasures" employed by subjects such as biting their tongues or pressing their toes to the floor during questions that are not incriminating.

    Seeking to uphold the court-martial of Scheffer, the government also asserts that the majority of the country's polygraphers have not been trained by the federal government and are not required to pass any uniform standards.

    Scheffer had passed a polygraph exam on whether he had used illegal drugs but flunked a urinalysis around the same time. He denied knowingly taking drugs, saying he may have ingested them innocently while working as a government informant.

    The federal government notes several states also ban polygraph evidence, and while there is no explicit federal provision prohibiting their use, federal courts traditionally have barred polygraph results. Twenty-eight states, including Maryland and Virginia, have submitted a "friend of the court" brief seeking to uphold bans on polygraph evidence.

    Polygraphs are different than other scientific evidence, some legal experts say, because jurors could view them as detectors of absolute truth. But advocates of polygraph evidence say it need not make or break a case – it should simply be included along with other evidence.

    In a ruling being reviewed by the Supreme Court, the U.S. Court of Appeals for the Armed Forces said that, under present standards for expert scientific testimony, an accused person still would have to show the validity of the polygraph evidence and back up the underlying theory that a lie produces a measurable physiological response.

    In the murder case Brisentine handled, the defendant's lawyer tried to convince prosecutors that the charges were baseless. But the polygraph thwarted him.

    When Brisentine asked the man questions about the details of the alleged murder, his respiration and sweat response skyrocketed on the computer screen. When it was over, Brisentine told the man, whom he declined to identify, that the polygraph indicated he was lying.

    Later, as he reviewed the vertical lines and dots on the computer screen, Brisentine said, "We watch very closely to see where the individual responds. . . . I'm not a gambler. I like things black and white."

    © Copyright 1997 The Washington Post Company

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