Lies Easier To Detect When Children Feel Guilty

How children lie

Children's lies are easier to detect if they feel badly about lying, a recent study by researcher Amy Leach suggests.

"To our knowledge, this is the first time anyone has studied whether the types of interviews used with children make lying easier to detect," says Ms. Leach, a PhD candidate in psychology.

The study published recently in the journal Law and Human Behaviour uses three types of interviews with children between the ages of four and eight.

Each interview begins with a researcher playing a game with the children, instructing them not to peek at a toy that is placed behind them, and then leaving the room. The interviewer returns a minute later and in a "direct" interview, simply asks the children if they have peeked or turned around.

During "promise" interviews, children promise to tell the truth before they are asked whether or not they peeked.

In "moral discussion" interviews, children are asked to identify lies and truth in various stories, and say whether lying is good or bad. Then they are asked whether they peeked at the toy.

Previous research had concluded that when children are asked to promise to tell the truth they are much less likely to lie, while after moral discussion they are just as likely to lie. But there was no evidence of whether the type of interview affected other people's ability to detect the lies.

The researchers felt that children who lie even though they have promised to tell the truth have to contend with the negative implications associated with deception, as well as the added stress of breaking a promise. This should make their lies easier to detect -- and it does, says Ms. Leach.

Customs officers and police officers, many of whom routinely interview children, were asked to take part in the study because of their work-related lie detection experience. However, whereas police officers have several minutes in which to question an individual, customs officers often have, in many cases, less than one minute to decide if a child is telling the truth. Despite the demand for split-second decision-making skills in the study, the results were consistent across both these groups and a group of university student interviewers with no expertise in lie detection.

However, there do not appear to be many common cues from children to indicate when they are lying or telling the truth.

"Unfortunately, there was no Pinocchio's nose," says Ms. Leach. "But the police officers, customs officials and university students who viewed the children were better able to detect lies if the children promised not to lie or considered the moral implications of deceit."

Follow-up studies will look at the reliability of individual performance in lie detection using both children and adult groups of potential deceivers.