We always advise reporting these cases to the police within 24 hours if you were not able to exchange details with the driver at the scene. However, the fact that you waited and then left a note is the basis for a defence. A witness usually tips off the owner with your registration number. The owner will then go to the police with a view to them providing your details. At that point the desk officer takes it as the reporting of two offences - failure to stop and failure to report. If they are being really officious they will throw in due care and attention as well. And then the wheels of justice start slowly turning. These offences will result in a fine and penalty points if you are convicted, but I have a colleague who specialises in getting these cases dropped before they go to court. Please send your email and telephone contact details to asklucy@honestjohn.co.uk and I will get her to call you to undertake a free initial consultation.