The subject of answering questions by the Constabulary has been brought up in several different threads in the past, so at the risk of repeating what has already been posted elsewhere;
If questioned by the Police after an incident/accident etc you are legally required to give your name and address, and nothing else!!!
AFAP members have some excellent advice given to them in the inside cover page of their diary which is distributed to all members and I quote from the first paragraph of the 'In the event of an accident or incident' section
"Say nothing until you have recieved advice."
'Nuff said.