3 points, standard fine. Ask for photo (which you are entitled to), if you can see your bald patch , then admit it was you. If you cannot tell who is driving, then say that it could have been you or Pat, you don't remember... However, you MUST provide the names of the possible drivers. If you stick to this story you "should" be okay, as I believe they are too scared to take such a case to court, as they have to prove your guilt and it could open the floodgates if it became public knowledge (as it would if it went to court) of how to put the onus on them.

However, it depends on how desperate you are to avoid 3 points and a £60 fine...