pediatric housecalls Robert R. Jarrett M.D. M.B.A. FAAP

How To Tell When Your Child Is Lying

All children in all countries of all races and sexes – lie. Can you tell when they are lying? Watch this and lying will never be the same again.

At two years of age 80 percent of toddlers will cheat and peek at a toy they were asked to leave hidden – and 30 percent will lie that they hadn’t peeked. At three years of age, 50 percent lie. At four years of age more than 80 percent lie and after that most lie.

Kang Lee
Researcher in children’s lying

Are children poor liars? Do you think you can easily detect their lying? Developmental researcher Kang Lee studies what happens physiologically to children when they lie. They do it a lot, starting as young as two years old, and they’re actually really good at it. Lee explains why we should celebrate when kids start to lie and presents new lie-detection technology that could someday reveal our hidden emotions.

Mr. Lee has devoted his career to understanding the development of social cognition and behavior.

With an international team based at the University of Toronto, he investigates the neurological and social basis of emerging social behaviors in young children. His two­-pronged research focuses first on how and when children develop the capacity to lie, to detect lies and to feel guilty about it afterwards.

The second focus of Lee’s research is facial recognition, which has led to revelations of when children develop the ability to distinguish races ­­and has helped explain why some people occasionally see Jesus’ face on a piece of toast.

We found that regardless of gender, country, religion, at two years of age, 30 percent lie, 70 percent tell the truth about their transgression. At three years of age, 50 percent lie and 50 percent tell the truth. At four years of age, more than 80 percent lie. And after four years of age, most children lie. So as you can see, lying is really a typical part of development. And some children begin to tell lies as young as two years of age.