I got a really good piuece of advice on this board once that went something like this:
Don't let them lie.
The thing is in our society we tend to want to give people a chance to own up to their mistakes as if by admitting the deed they are half way towards making amends. But that is not not really the case. It doesn't really make it better that he says "I ran into her on purpose, I just didn't think it would hurt her." Now you are left with the fact that you have a kid who openly admits they engage in rather sopciopathic behavior. I mean even though we give murders a plea bargain when they admit it, it doesn't really make the family of the victims feel better about the murderer to know he admitted it, ya know?
So, I don't know how to punish lying but I have stopped giving DS room to lie and the lies have gone down SIGNIFICANTLY since starting.
Instead of "Did you run into your sister on your bike?" "
Why did you run into your sister?" and then if he says "it was an accident." then thw logical consequence is clear, he needs to take a bike safety class and can't ride until he does. If he bold face lies and says "I didn't, I don't know what you are talking about." then I think it would be appropriate and logical to take away the bike as it seems to be clearly giving him temporary amnesia or perhaps road blindness and that is really dangerous and needs to be checked out by a doctor.
An example from last week for me:
DH told DS to stop throwing his cousins toys in the pool. DS looked at DH and threw the doll in the pool. DH almost flipped a LID, and I said "Why didn't you listen to Daddy and stop? Why did you ignore Daddy?" he said "I didn't hear him?" "I said if that's true, then you need to come out of the pool for the next two days to give your ears time to dry out and if that doesn't help we'll go to the doctors." "Noooo I was teasing. I'm sorry. I did hear daddy. I just really wanted to do it!"
Uh huh...now
that is easier to punish, ya know? Apologize to Daddy, retrieve the toy, apologize to your cousin, and stop fooling around.
So I guess trick them into the truth by A) not pretending you don't know he did it if you KNOW he did it and then B) giving a logical consequence for their answer and see if their answer changes.
Anyway, that's what works here.

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