One of my friends went out out the other night and borrowed her sisters ID after a mix up, she thought her sister had said she could borrow it when she hadn't, she then got it taken off her at a club and the club are passing it over to the police her sister wants her to go to the police with her and explain what had happened, what's the worst consequence by law for using someone else's ID to get into a club? (for a 17 year old)

Did the Police file charges or this just a case of going down to the Police Department and picking up the card?

You are aware that even if the sister GAVE permission to use the ID this is, in fact, a criminal act. If the sister gave permission she could also be charged.

I think its just going to pick up the card I'm not too sure if they do file charges what are the consequences? I know about the giving permission but it was a big missunderstanding the sister said something to her that inplied she could borrow it but but she didn't give her permission and my friend misunderstood her.

I see all sorts of legal questions, such as how the person got the sister's card, how such a misunderstanding could occur. None of this probably matters. I doubt there will be charges filed. I would guess there will be warnings and a lecture.

If no one was arrested/charged at the scene I would "guess" (again) this is simply to pick up the ID.

If it is how you say, and it is just a warning will my friends parents be notified about the incident? And if my friend has a previous warning for shop lifting will this affect the situation?

Yes, the warning for shoplifting certainly could enter into this.

I doubt her parents will be notified. If so, she would have been advised to bring them to the Police Station with her.

However, if she's used her sister's ID in this fashion, has been picked up for shoplifting, maybe the Police will decide the parents should know.

- Hard to say.