Putting Monica Lewinsky on the witness stand in President Clinton's impeachment trial will let senators look her in the eye - but psychologists say that's a chancy way to judge someone's credibility. In fact, studies show that to spot liars through their demeanor, most people might just as well flip a coin. People can control their face. House prosecutors want Lewinsky, presidential friend Vernon Jordan and White House aide Sidney Blumenthal to testify in person at the Senate, or at least for the Senate as a whole to watch the videotaped testimony about Clinton's efforts to hide his affair with Lewinsky. Only Secret Service agents could consistently spot a deceiver.
Some people simply are great liars.
They know people think a liar won't look them in the eye - so they make sure to look someone in the eye while telling a falsehood. Verbal clues tend to be better indicators of lying because they're harder to control, Zebrowitz said. Someone's voice pitch might get higher, or they may pause more often than usual. In his book, Telling Lies , Ekman said he often wisecracks that the criminal justice system seems designed to make it hard to spot liars by their demeanor. Suspects have plenty of time to rehearse their answers and may have repeated a false account so often they start to believe it, he wrote.