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When Does Lying Begin?

How early do we learn to lie? And what purpose does it serve in young children?

Whether we choose to admit it or not, lying is a part of life (would I lie to you?). From casual "white lies" to more complicated scams and major deceptions, lying seems to be at the root of a bewildering number of political and economic scandals. The question of whether someone is telling the truth seems to comes up time and again in many of our social interactions as adults and recognizing lies becomes a major challenge.

But how early do we learn to lie? And what purpose does it serve in young children? While measuring lying behavior in young children through laboratory experiments has its own limitations, previous study results suggest that lying behavior can be seen in children as young as 42 months. Anecdotal evidence provided by parents and caregivers suggests that lying behavior can be seen in children who are even younger, although it is somewhat different from the lies we tell as we grow older.

According to a developmental model of lying first proposed by Victoria Talwar and Kang Lee, children around the age of 2 to 3 years begin by telling primary lies that are designed to conceal transgressions but fail to take the mental state of the listener into consideration. Around the age of 4, children learn to tell secondary lies which are more plausible and geared to the listener's mental development. By age 7 or 8, children learn to tell tertiary lies which are more consistent with known facts and follow-up statements.

Since the executive functioning skills needed for lying are already in place for chldren as young as 2, it is probably not surprising that parents have reported seeing their own children attempt lying behavior at that age. In 1877, Charles Darwin suggested that children as young as 30 months are capable of lying after seeing his young son trying to deceive him. More recently, a team of British psychologists used a natural observation method to spot 37 examples of lying behavior in a 30-month-old child. Child researchers at the University of Waterloo reported that 65 percent of 2-year-olds and 94 percent of 4-year-olds lied at least once.

While naturalistic observation by researchers is more impartial than the anecdotal evidence provided by even eminent scientists like Darwin, there are still problems involved in ruling out other possible explanations for what the researchers are seeing. Laboratory studies suggest that children are capable of deceiving people (such as learning to hide toys) but it is debatable whether spontaneous lying can be effectively studied under laboratory conditions.

There appears to be a link between a child's cognitive abilities and their ability to lie successfully. Along with executive functioning, children need to be capable of inhibitory control, i.e., the ability to suppress a response while completing a separate goal. A good working memory is also needed since children need to be capable of retaining details about the lie and the truth. Research looking at lying in young children suggests that inhibitory control is especially important since children with poor control are not effective liars while working memory may not be as useful.

A new study published in Developmental Psychology examined lying in 2- and 3-year-old children and some of the cognitive skills involved with deception. Conducted by Angela Evans of Brock University and Kang Lee of the University of Toronto, the study used a series of executive functioning and verbal tasks as well as two deception tasks to measure lying behavior.

The first deception task involved children being invited to play a guessing game in which a toy was placed behind them and they were asked to guess they toy from a characteristic sound (such as quacking if it was a toy duck). After children successfully guessed two toys, the experimenter pretended to get a storybook and the children were asked not to peek at a toy that had been placed behind them (a hidden camera monitored their behavior). When the experimenter returned with the book, children would then ask if they had peeked.

The second deception task involved a gift delay in which children were presented with a gift bag and asked not to peek while the experimenter left the room to get a bow. Hidden cameras monitored what the child did while the experimenter was absent. After three minutes (or sooner if the child peeked), the experimenter returned to the room and asked if there was any peeking.

On average, 80 percent of all children peeked while 40 percent lied about it afterward. While the youngest children (aged 25 to 28 months) were the most likely to peek (94.7 percent), they were also the least likely to lie when questioned (33 percent). Conversely, older children (aged 43 to 48 months) were least likely to peek (62.5 percent) and most likely to lie when questioned (90 percent). Tests of executive functioning and working memory also showed that children with better cognitive skills were more likely to tell lies.

Based on their results, the authors suggested that children as young as 2 years old were capable of spontaneous lying and that lying behavior rose dramatically by the time they were 3 years old. The authors also suggested that this was not because younger children were more honest but that they were less able to carry out the complex cognitive tasks that went into telling lies. In other words, children with better cognitive abilities are capable of telling better lies. All of which implies that lying is as much a developmental milestone as any other cognitive task (if not the sort that parents are likely to brag about).

But is lying always negative? It's tempting to argue that lying is also linked to creativity since the ability to create fiction often relies on the same cognitive skills that go into telling a successful lie. As children develop in their cognitive capacity, the ability to balance more than one reality in their head (which is what liars do when they create a fictional version of events to match with the truth) becomes easier. It also means being able to recognize the difference between fiction and reality, much like what they watch on television as well as being able to create new stories.

So the next time you catch your child in a lie, spare a thought to the complex cognitive skills involved before handing out a punishment.

More from Romeo Vitelli Ph.D.
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