Why Do Children Lie, Cheat, and Steal?

Know a few little delinquents? Don’t get out the handcuffs (yet)—it’s normal. With some shrewd police work, you can get to the bottom of why they’re committing those petty crimes.

Remember the famous story about a young George Washington who could not tell a lie? What a whopper. The more realistic tale is the one about Pinocchio—the would-be boy who lied until the web of deception was as plain as the ginormous nose on his wooden face.

It’s the truth: Almost all kids lie. They might also cheat and steal. But that doesn’t mean they’re headed for juvenile hall. To learn the boundaries of acceptable behavior, a child occasionally has to steamroll through them; doing wrong is an essential part of how a kid learns—with parental guidance—to do right. Here’s what’s normal (along with what might be more troubling) and how you can be soft on the little criminal but hard on the crime.


Lying may be the most common underage offense. A kid will start telling you things that aren’t true long before he even realizes it’s naughty (for instance, that chocolate-smeared baby who shakes his head when asked whether he ate the cookie). When he starts to understand that he’s bending the truth—as early as age three or four—it’s actually a sign of cognitive development. That’s because to purposefully tell a lie, you first need a grasp on reality. Next you need the wherewithal to create an alternative reality, and finally you need the brainpower and the gumption to try to convince someone that a fiction is the truth.

“When preschoolers first lie, they’re testing out a new ability,” says Victoria Talwar, a professor of developmental psychology at McGill University, in Montreal, who has done extensive research on kids and lying. “They’re realizing they can have thoughts, knowledge, and beliefs all their own.”

One study at the University of Waterloo, in Ontario, that observed kids at home found that some four-year-olds lied once every two hours; some six-year-olds lied at a clip of every 90 minutes. Lying typically peaks between the ages of 6 and 10; it decreases as kids grow older and start to understand the consequences of lying and the likelihood of getting busted.