I wouldn't worry about it. I've had other cars 'tap' my rear bumper loads of times and, just like the driver you refer to, I've simply shrugged my shoulders and driven on. (I once got hit three times, by three separate taxis, in under 10 minutes in central London!).
To actually answer your question, the council are obliged (under the Data Protection Act) to provide you with a copy of the CCTV footage if you write to them (addressing your letter to the Data Protection Officer), providing details of the footage required, submitting proof that you were the driver of the rear vehicle (using, for example, your insurance certificate) and enclosing payment of �10.
Chris