Does your teenager lie to you? How do you know?
The short answer to this question is YES; your teenager lies to you. To quote that cynical TV medic, House, "Everybody lies". Can you honestly say that you have never lied to your teenager? Maybe you do not see it as a lie, more of an omission of the truth, what they do not know will not hurt them. Well, unsurprisingly, your teenager operates on much the same system. They know that there are certain things that parents go loopy over, such as drinking, sex and fighting. So, if you ask them where they have been, they will truthfully tell you they were out with friends and had an ok time.
What they will not tell you is that they got into a club for over 18's met some boys and then felt really uncomfortable and left. You would be secretly glad to know that their common sense asserted itself, but if they told you what they had done, you would have focused on them getting into a club they are too young for in the first place and there would have followed an almighty row. Teenagers know that some things are best left unsaid.
However, the issue is one of trust and you need to make sure that your teenager trusts you enough to risk your wrath and tell you certain things you will not like. If your only reaction to the truth is to yell at them and ground them forever, they will soon stop telling you the truth. If you react to the first part of what they tell you, "Mum I tried smoking a joint tonight", with fury and hysterics, without waiting for the second half, "and it was horrible and I'm never going to do it again!" you risk alienating your truthful child and missing an opportunity to discuss with them, in an adult fashion, something that is serious and important.
Do not take the line that they must tell you the truth because you are the parent and they are obliged to, it does not work like that. You actually have to earn their respect in order to get them to trust you enough to discuss sensitive issues.
Teenagers will generally talk to their friends before they talk to their parents; they assume their parents will disapprove of what they do or think. To enable frank and honest discussions with your teenager, you should not lie to them; if they discover a lie they will feel betrayed and lose respect for you. Assume that you do not know everything your teenager gets up to and that with some things you might be better off not knowing. By all means discipline your teenager when they do something wrong, but discuss what they have done calmly and learn lessons from it. Do teenagers lie? Yes, but hopefully not about the really important things, and you can forgive them when the truth comes out.