Most parents know that angry feeling they get when they realize their teen is lying to them, but the child will simply not admit it when caught. Many parents do not know how to react. Some teens believe if they protest their innocence long enough, parents will begin to doubt themselves. If you are sure your child is lying, however, it is important to deal with the situation immediately by finding out why your teen feels compelled to be dishonest, discussing your feelings about the importance of trust and honest communication, and by making clear the consequences your teenager will face if you catch him or her lying in the future.
Learning by Example
Although your child's strongest influences are most likely peers, they do see how you behave and will often model their behavior and form ethical and moral beliefs based on your actions. If you have lied to your child in the past, you may have some issues to deal with beyond simply setting consequences. If there is one behavior that turns teens off, it is adult hypocrisy. If they see their parents taking short cuts that defy their stated ethical values, children quickly absorb this information and see that what is said is not what is always done. This is not to say parents must be perfect, but you also cannot say to your child, "I'm adult so I can lie, but you can't." Teens simply don't buy that argument.
Why Did You Lie?
Rather than instantly start to lecture your child about why lying is bad (you can be sure they know lying is not a good idea), first ask them to explain why they thought lying was the best choice in this situation. You can explain to them that lying is unacceptable, but if there is a reason why your child felt compelled to lie, you want to know it so you can possibly eliminate any misunderstandings. This is not to say they might have a good reason for lying, just that they might feel they had a good reason for lying. Did your child lie about failing a test because he or she thought you would tell them they are stupid? Did your child lie about a party because even though it was an innocent party, they know you absolutely forbid parties, period? Did your child lie about a boy they are dating because they know you don't like kids from "that side of town?" If your child has a reason for lying that might be removed through discussion and open communication, you remove that "excuse" in the future.
You may find your child lied simply because they knew the behavior was wrong and they didn't want to get caught. This will mean you need to let them know in very clear terms what behaviors are unacceptable and what the consequences will be, not only for repeating that behavior, but for lying about it. These are two separate events that will lead to separate sets of consequences.
Should You Trick Your Teen to Catch Him or Her Lying Again?
This isn't the most honest way to deal with a teenager who is lying. It is, in effect, a form of dishonesty too. The direct approach that includes a clear set of rules and consequences is always best. A good way to keep track is to increase temporarily the requirement that your child "check in" with you to let you know where he or she is, when he or she will be home, and who he or she is with at the time. This increased supervision will make your adolescent acutely aware that if they do not earn your trust, they will not get your trust. If you see that your teen is genuinely working toward rebuilding trust, you can give him or her more personal responsibility and not require as much "checking in."