“What’s the Truth About Polygraphs?”

Madelaine Vitale reports for The Press of Atlantic City (New Jersey). Excerpt:

The prosecution’s key witness in the Lloyd Massey II triple-murder trial failed a polygraph.

The jury never heard about the lie detector.

While polygraphs are considered valuable tools in helping law enforcement rule out potential suspects in crimes or focus on a particular person, they rarely play a key role in court.

The results of the tests are admissible in some federal circuits and some states, but only if the person taking the test signs an agreement saying it can be used for or against him in court.

Some jurisdictions ban polygraph results as evidence. Test results also cannot be used as the reason for a motion for a mistrial or a retrial, according to the American Polygraph Association.

Like the Massey case, there have been other trials in which key witnesses for the state failed lie-detector tests, but their testimony still was presented to the jury.

In Utah, in June 2001, Elroy Tillman, the state’s oldest death-row inmate, argued prosecutorial misconduct because attorneys for the state did not turn over the failed polygraph results of his accomplice, Carla Sagers.

The defense attorneys argued that Sagers’ inconsistent testimony and failed polygraphs should be used as evidence for the judge to stay the defendant’s execution. The decision is pending, but attorneys anticipate the judge will sign another death warrant.

Despite many court rulings that polygraphs results are not admissible, municipalities all over the state often use polygraph examinations.

In a case in June 2001, in which two women made allegations of sexual assault by a Camp County, Texas, police officer, two women took polygraph tests and passed. The officer, William Henson, took a polygraph test and failed. He then admitted his guilt and was convicted.

The Supreme Court has said the examinations raise the issue of a person’s Fifth Amendment protection against self-incrimination. The high court still has not ruled on the admissibility of polygraphs, so the process varies in different federal circuits.

Proponents of the polygraph say studies show that the test, which hasn’t changed much since the 1920s, has an accuracy rate of 85 percent to 95 percent. Opponents say results depend on who is giving the test, and that the examiner can cause a person to fail a test just by the questions asked.

Sgt. Chris Pukenas, one of three members of the New Jersey State Police Polygraph Unit, travels all over the state to give these examinations, in many cases for municipalities who do not have their own examiner or just prefer to use the State Police unit.

Pukenas gave the test to Jesse Timmendequas, who was convicted of raping and killing 7-year-old Megan Kanka in 1994 in Hamilton, Mercer County, after luring her into his home with a puppy.

He couldn’t discuss the results of that test because the case is under appeal, but there were reports that Timmendequas failed the polygraph.

Pukenas stands behind the effectiveness of the tests.

“The tests work. They cut out countless hours of police work and often rule out potential suspects and sometimes help to identify a particular suspect in a crime,” Pukenas said.

“I had a man indicted for murder. He insisted he wasn’t at the crime scene. He insisted he didn’t do it,” Pukenas said. “He passed the test and a few days after the test police captured the real killer.”

Pukenas, who is nearing his 14th year in the Polygraph Unit, gives anywhere from 100 to 125 polygraphs a year. He said only about 10 percent of his polygraph results are tests where the subject signed a waiver that the results could be heard in court.

That doesn’t mean polygraph results do not affect how a case is presented.

Pukenas said often the questions asked and statements taken by law enforcement before the polygraph is given are admitted into evidence. He testifies on what was asked and what the witness or the defendant said.

But the jury cannot have knowledge of the polygraph in those instances. If Pukenas got on the stand and muttered the word “polygraph” it could lead to an immediate motion for a mistrial because the test has the potential to sway the jury, he said.

Some opponents of the polygraph have a Web site called Antipolygraph.org where critics cite reasons that polygraphs should be banned. These reasons include: no scientific basis for the polygraph, deceptive techniques used by the examiners to make the person taking the test fail, and how a person, if taught properly, can beat the polygraph.

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