When a child is accused of doing something their first reaction is to lie, deny, place blame somewhere else. For small day to day issues I don't bother to accuse anyone. For example, I don't ask who made a mess, I simply say that whoever made a mess needs to clean it up. Then I walk away. I took awhile but the kids have come to realize that if they actually clean up their mess then nothing more is said. This prevents a lot of small lies throughout the day.
If I know that a child did something, I don't ask them if they did it. Why give an opportunity for them to lie. I simply tell them that they did something and go from there. I have some kids who want to deny and I try not to get caught up in the argument. It is amazing how some children will deny things that you just saw. I just got new glasses, I can see.
We have the "do over". If I do ask a child a direct question and I know that they are lying to me I will slow down and have the child think about their answer. They are allowed to change what they just said out of habit. If they do then it is as though they didn't lie the first time. This is important because...
We have a different consequence for lying than we do for the infraction. I will tell them what the consequence is for the infraction and then what it is for the lie. Two different consequences. Many of my kids have come to realize that the consequence for the infraction is less than the lying. Often the consequence for behavior is so simple; separate, go inside, go apologize, stop the game for a bit, go take care of it, don't do that again, follow the rules. Small incidents that are not worthy of a consequence for lying.
I have read that you shouldn't take lying personal. I agree but find it very hard. I am sure that I have said many times that the lies are questioning my intelligence. One time I asked Michelle how she thought that she would get away with some of her lies and she said that she has lived with some stupid people. I told her that she doesn't now and she agreed.
I realize that I will not catch every lie. I tell all my kids that some days I am weary of the lying so I just ignore them. However, the important thing is that they know in their heart that they are lying. In the end they have to decide what makes their heart feel best.
Our current situation......
Our school therapist said to find something that is inconvenient for the child. For Michelle I picked matching socks for lying to the police. I consider lying to the police to be a pretty big offense. Michelle does not like to match socks.
This is her pile after she said there were no more matches. I sat down for a minute and found 14. There are many matches left.
On a side note, I tried doing the switch on Michelle. I offered her two choices for lunch. When she picked one I gave her the other saying that she lied so much I thought that she really wanted the other. It didn't work, she said she did. Ha, thought I would try it.