U.S. POLYGRAPH LAW

In 1922, a trial judge in Washington, DC refused to let Marston (seated on right) testify that his test had exonerated James Alphonso Frye (center) who had retracted a confession of murder. This refusal was upheld on appeal to the Court of Appeals of the District of Columbia. The terse opinion in Frye v. U.S., 293 Fed. 1013 (1923) set the rules governing the admissibility of scientific evidence in criminal trials for the next eighty years. The court declared that experts might only testify about a scientific matter that was “sufficiently established to have gained general acceptance in the particular field in which it belongs.” On the basis of this precedent, the lie detector evidence has been largely excluded from criminal trials to the present day, although its use has been allowed in many other settings.

33. In 1998 the U.S. Supreme Court heard United States v. Scheffer, 523 U.S. 303 (1998), a case involving a military officer who had been denied the right to introduce polygraph evidence that seemed to exonerate him for failing a drug test. The justices listened to oral arguments about the reliability of the lie detector. But in the end, Scheffer was decided on narrow grounds. Writing for an 8-1 majority, Justice Clarence Thomas upheld the prerogative of the appropriate rule-maker (here the President in his capacity as Commander in Chief) to ban the polygraph so long as he provided minimal rationalization. Yet only three justices (forming a conservative minority) agreed with the remainder of Thomas’s opinion: that the polygraph threatened to usurp the jury’s role in making assessments. The four partially concurring justices and lone dissenter (forming a liberal majority) defended the jury’s ability to assess all forms of evidence, including scientific evidence, and they pronounced themselves troubled by America’s double-standard for the polygraph.

The muddled ruling left lower courts free to admit the polygraph, as some have cautiously begun to do. As of 2003, the Fifth and Ninth Circuits have left the use of the polygraph up to the discretion of the district judge, though not many trial judges have allowed the evidence. New Mexico continues to be the only state to allow the polygraph in criminal cases without stipulation.

For the Scheffer case, see the opinion. http://supct.law.cornell.edu/supct/html/96-1133.ZS.html

For written opinion and oral arguments in Scheffer, see Oyez.
http://www.oyez.org/cases/case/?case=1990-1999/1997/1997_96_1133