Had this with my sister, go to the old bill, you complete a form and they send it to your insurance with all the details (your not allowed to seem them).

Oh, and they also issue a notice to prosecute, that usually makes them shit their pants, and in my sisters case, theguy called her being all smarmy saying

"hi, just wondered why you haven't contacted me, i was worried about you, oh i must have goten a number wrong, and by the way, the police want to do me for leaving the scence of an accident, can you let them know i didn't"

My sister got paid out straight away

The guy had given a reg with one letter out, and the number was his, but when we called it, he said, sorry no mr smith here . the police were spot on, tried a couple of varients on the reg until they got a silver focus, registered to a mrs smith in that area, he had written J and it was a U (he wrote J deffo, not a slip of the pen)

I would say it is the police letter that makes them shit their pants