U.S. Judge Rejects Lie Detector Evidence

A federal judge has ruled that the results of polygraph tests are still not reliable enough to be admitted as evidence in courts of law.

“Polygraphy has not achieved general acceptance in the scientific community for courtroom use,” said U.S. District Judge Gary L. Taylor.

In ruling against the admissibility of polygraphs, more commonly known as lie detectors, Taylor denied a motion for a new trial filed by a 50-year-old Miami man sentenced to 22 years in federal prison for cocaine possession.

The man, Frank Javier Cordoba, claimed that Taylor, who presided at his trial, had improperly prevented the jury from hearing that a lie detector test he took after his 1995 arrest showed that he was truthful when he told authorities he did not know that a van he was driving in Santa Ana contained 300 kilograms of cocaine.

Last year, the U. S. 9th Circuit Court of Appeals overturned Cordoba’s conviction, saying that the automatic and total exclusion of polygraph evidence from federal trials was no longer proper.

The appeals court instructed Taylor to decide whether Cordoba’s favorable polygraph test could have made a difference in his trial.

In ruling that it would not have changed the trial’s outcome, Taylor also addressed whether polygraphs should be used in courtrooms at all.

That question has recently surfaced in court actions across the nation, including the U. S. Supreme Court, which is expected to decide later this year whether a criminal defendant has a constitutional right to present evidence of having passed a polygraph test.

Polygraphs have been excluded from federal courts since 1923, when a federal appeals court held that results of a blood pressure machine--a crude precursor of the modern polygraph--could not be used in court.

But the Supreme Court relaxed the rules involving admissibility of scientific evidence in 1993, declaring that federal judges need only conclude whether scientific evidence is “relevant” and “reliable.”

After that ruling, several attorneys sought to have lie detector tests admitted in trials, noting that polygraph testing had greatly improved over the last decades. They cited statistics showing that the FBI administers 35,000 polygraph tests a year and other studies concluding that polygraphs are accurate 90% of the time.

But Taylor insisted that there was still too much uncertainty involving polygraphs.

While “polygraph [testing] has emerged as a useful technique for many diagnostic or investigative uses,” the judge said, “there is no general acceptance in the scientific community for use of polygraph evidence when reliability is critical, as in courtroom fact determination.”

“There are no controlling [national] standards to . . . provide a court with a yardstick by which a particular defendant’s examination can be measured,” Taylor said.

Assistant U. S. Atty. Elizabeth Abrams said Wednesday the government is pleased that Taylor “recognized the use of polygraphs as an investigative tool, as opposed to being used in court.” Cordoba’s attorney, Deputy Federal Public Defender Craig Wilke, declined comment but has filed a notice to appeal Taylor’s ruling.

Davan Maharaj can be reached at (714) 966-7700 or by e-mail at davan.maharaj@latimes.com