As parents we want to believe that our children will always tell us the truth and it is a difficult moment when we realize our child has deliberately lied to us. Lying is a normal part of childhood development. Children may begin telling "lies" around the age of 5 in order to avoid disappointing their parents or to avoid punishment. Usually, lying around this age, and the occasional white lies don't indicate a serious problem. Even so, lying should be addressed and steps taken to correct the behavior before it does become habitual or chronic and causes problems at home, in school and in friendships.
Over the years, many parents have written to me about their children lying and wondered if this was simply part of ADHD, a sign of another disorder such as oppositional defiance disorder or a behavior issue outside of ADHD. According to Dr. Peter Jaska, in an article that appeared in Additude Magazine, "Some ADHD kids may not be dishonest as much as they are victims of uncontrolled ADHD symptoms."
Some children (and adults) with ADHD have executive functioning deficits. Executive functioning, according to the National Center for Learning Disabilities, "involves activating, orchestrating, monitoring, evaluating and adapting different strategies to accomplish different tasks...It requires the ability to analyze situations, plan and take action, focus and maintain attention and adjust actions as needed to get the job done."  Those with ADHD may have problems with communication because of their executive functioning deficits. For example, the inability to correctly analyze a situation and respond appropriately can lead to miscommunication. Imagine a child who "zones out" and misses part of a conversation. In order to feel adequate, he makes up an answer when called upon to make it sound as if he knows what is going on. Has he lied? Has he intentionally misled others? Probably not.
Another example may be a child with ADHD who often feels inferior to his peers. He feels as if he isn't "good enough" or doesn't fit in. He makes up stories to make himself look better in his peer's eyes or he exaggerates his actions to feel more important. He is trying to protect himself from further hurt and humiliation and so he lies. This same type of lie can be seen when a child with ADHD doesn't want to get into trouble. He knows he forgot his homework, again, but doesn't want to see the disappointment in your eyes or in his teacher's face. He wants to be seen as competent and so instead of saying "I forgot," he makes up a story about how he completed his homework but left it on the kitchen table, or that he did the homework but just lost it.
Impulsiveness also adds to the problem of lying. When faced with a crisis - both small and large - your child needs to think quickly. He needs to come up with an answer or an explanation. Not wanting to get into trouble, your child impulsively tells you a lie to cover up a mistake or to avoid further problems. As with many children with ADHD, he may not connect future consequences with the current situation. When acting impulsively, he is thinking "in the moment;" there is no past and there is no future. The only moment is now and in this moment, a story is much better than the truth.
Although lying should certainly be addressed and dealt with, it is also important to look at the underlying reasons for the lying. Are symptoms of ADHD not being controlled properly? Are there ways you can help your child better control symptoms to eliminate the need to lie? When your child is lying, therefore, your reaction needs to be twofold. It needs to deal with the actual behavior of lying and you need to look for the underlying reason and help your child better manage symptoms of ADHD. If lying has become a habit, it may be time to review your child's treatment plan and decide where it can be tweaked and adjusted to help your child better manage symptoms.
 "The Truth About Your ADHD Child's Lying," 2009, Peter Jaska, Ph.D., Additude Magazine
 "What is Executive Function?" 2010. NCLD Editorial Staff, National Center for Learning Disabilities