How to deal with lying

[MoodyMargaret11]

Have a teen SC, largely get on well and no major issues currently. However he used to lie A LOT when he was younger, sometimes to make himself look superior, other times to get his way, or to avoid taking responsibility/consequences to something he'd said or done.
Although he is much better now, there are sometimes situations I find difficult to handle. When he's said something mean to my DC but no one else around, so when I try to ask him about it and work things out, he flat out denies and acts like his sibling is the one lying or mishearing things. His dad is useless as he puts it down to a misunderstanding, mis-remembering or no big deal. But it bothers me and I feel pretty disappointed that he'd treat family like this and also that he's happy to just lie.
Is it better to just stop addressing these things with him altogether, and let his relationship with my DC take it's natural course? And just support DC privately?
The kind of things he says are not something horrendous, but still hurtful. I dont really want any drama, just say Sorry and move on. But becomes a bigger thing when he doesn't.

Yes it needs to be dealt with..Get your partner involved..Do not ignore it. A few examples of what he's said could be helpful and in particular cases where the lies are causing hurt to your children. Make a big deal of it. Honesty counts

I think it's really important that you get to the bottom.of why he feels the need to lie.

As pp said honesty is really important . Lying makes a person unreliable, untrustworthy and unattractive and permeates all aspect of person 's life and has wide reaching repercussions. It really needs to be addressed before it becomes ingrained.

Is it always and only a he said she said with your child? Not historically, but currently.

How do you know he’s always lying and your child isn’t lying sometimes as well?

I wouldn’t ignore it, because your DC needs to feel protected and believed. But I also wouldn’t keep trying to force SC to admit it or apologise if denial is his default response.

Instead, stop focusing on proving what was said and focus on the family standard: “I’m not going to argue about exactly what was said, but we speak respectfully to each other in this house” type of thing. That avoids turning every incident into a battle over who is lying.

Your husband minimising it probably reinforces the pattern, even unintentionally. SC learns denial works, while DC may start feeling there’s no point speaking up.

Support your DC privately - “I believe you felt hurt”, “You don’t deserve that” etc, but avoid creating a “bad child / victim child” dynamic.
The key is calm, consistent boundaries - not interrogations or trying to extract apologies.

Good luck 🤞

First, it’s important to understand why he is lying. The reason can also depend a lot on his age.
I’d recommend two good books on this topic: The Truth About Lying and Why Kids Lie by Paul Ekman. Both explain in detail why children lie and give practical advice on how parents can respond and improve the situation.
Hope this helps.

Thank you @NorthernSpirit that sounds like an excellent approach, minimal blame and confrontation, and still handled in a sensitive way.
Over the years I've tried to use similar tactics, but lying really annoys me and his dad has always been soft with him, even when the lying is obvious often he wouldn't confront him about it. Fortunately, nowadays seems only occasional but I dont think I ever trust entirely what he says.

@flippap thank you for the suggestions, I will have a look. I know there's always a reason behind, doesn't make it better but some understanding helps.