Can you tell a lie from looking at a face?
It's a hotly debated question in the legal community, as the courts decide whether a Toronto sexual assault complainant will be allowed to wear a niqab while testifying.
While the panel of Ontario Court of Appeal judges is not expected to rule on the matter for several months, comments made during the hearing suggest they will side with the complainant, known as N.S. While the decision will also weigh cultural observance and courtroom procedure, critics such as Frank Addario, a lawyer representing the Criminal Lawyers Association, argue that observing facial features is vital to cross-examination. The defendants in the case have also argued that allowing the complainant to wear the full veil over her face will threaten their right to a fair trial, since they can't face their accuser and because the truthfulness of her testimony would be harder to gauge.
But as it turns out, the role that facial features play in revealing deceit is just as divisive among lie-detecting experts. There is no consensus among fib finders about which body parts matter most - and whether you should let instincts or experts inform your search for the truth.
According to Gini Graham Scott, author of Playing the Lying Game, body language is everything. The Santa Barbara, Calif.-based sociologist and consultant says that physical cues given during a polygraph test can indicate untruths more accurately than actual test results.
In other words, what shows up in the face is more important than what shows up on the machine.
A veil would obscure, for example, "blood in the neck," Ms. Scott says. "If there seems to be a restriction in the face or the neck," particularly if it changed during an important question, that would be one indication of lying, she says.
Experts such as Paul Ekman, professor emeritus of psychology at the University of California San Francisco and author of the book Telling Lies, says the ability to deceive is, in fact, measurable in facial cues.
"Facial expression is the single most important source if you're going to detect lies," says Dr. Ekman, who has trained Canadian judges and RCMP officers in the art of lie detection. His studies have shown that detection based only on facial expression has a 70-per-cent success rate. The percentage, he says, climbs to 90 when other factors such as voice and gesture are also accounted for. A veil would completely cover facial microexpressions, says Dr. Ekman of the tiny muscular movements he trains law enforcement officials to spot.
A niqab does leave the eyes exposed - the windows of the soul in popular culture. But eyes don't reveal everything, according to some experts. Even when eye contact is paired with body language, the signals can be misread.
Richard Litkowski, adjunct professor at Toronto's Osgoode Hall Law School, also practises criminal law. "It's dangerous to rely on demeanour alone," he says, especially if there are cultural differences involved. We tend to overestimate our ability to detect lies through facial cues, he says.
Mr. Litkowski cites a 2007 case from the Ontario Court of Appeal, in which "a conviction was overturned because the trial judge failed to take into account cultural differences that affect demeanour." Namely, eye contact. The judge mistook a lack of eye contact for the passivity of the witness, who was born and raised in Sudan, where eye contact is perceived differently.
Instincts can be an occupational hazard of the legal profession and have led to wrongful convictions.
"Most trial lawyers have faith in their ability to take note of physical cues they perceive as they give evidence," Mr. Litkowski says.
They tend to act on intuition gained through years of law, but "demeanour evidence should be tempered by the limits of our ability as human beings to be accurate lie detectors."
If there is a human lie detector, it may be Dan Crum, a former CIA investigator and polygraph examiner.
Mr. Crum, who regularly does speaking engagements as "the Dating Detective," says that physical cues given off by the rest of the body, the parts other than the face, are the real informants. There are enough bodily and verbal clues to deception to fill Mr. Crum's book Is He Lying to You?
"Most things are not in the face," he says. One common misconception is that patterns in eye movement can indicate what the person is thinking about. Mr. Crum doesn't buy it. What you need to look for is deviation in normal behaviour, he says, what he calls WIN - "what is normal." Once you establish a person's baseline by observing how they respond to trivial questions, he says, "the most global way of analyzing is if they do something that isn't normal." This could be an odd gesture, change in posture or a hand to the mouth while speaking that wasn't there before. But this doesn't always help.
"The most common question I get asked is, 'How can I tell if someone is lying to me if I can't see them?' " he says. Mr. Crum wrote The Faceless Liar, an e-book, in response to this question, usually posited by suspicious spouses who are wary of their partner's texting habits. He says the same WIN technique can also be used for changes in voice and phrasing.
But don't just memorize the tips, Mr. Crum advises. Use your instincts, look and listen for yourself. In other words, truth seekers beware. Because, he points out, liars can be just as resourceful.
"They've read about what appears to be truthful."