I can only assume different companies behave differently. My old mk1 Sport was reversed into in a car park. A helpful bystander left me the van details under my windscreen wipers. I informed my insurers and also the police. After the police interviewed the guy and decided to proceed no further (leaving the scene etc), no claim was eventually made (as I sold the car). On renewal, my premium was hiked up as in their exact words "statistically, if you have been hit once, you are more likely to be hit again". What a load of *****, they are robbing bartstewards. Anyway, after some heated phone calls, they subsequently removed the details from the file and dropped the renewal back down (I moved companies as a result anyway). I can therefore see both sides of the coin here, and you just need to go the route you are most comfortable with. If it were down to me, I would keep schtum though.
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