I always take pictures, always. I have also a disposable camera in my car just in case I forget my phone to take pictures with. It never hurts to have too much detail especially in a clear cut accident.

Afterwards the other driver can't claim differences which are documented with pictures.

Dave wrote:

The case eventually ended up it court where my brother thought that the other driver was at fault...........unfortunately that wasn't the case as at that time there was nothing in law that stated you had to be in a particular lane to turn right or left at a roundabout.

I know judges & the like normally refer to the highway code for guidance, but if he or his insurers have a good solicitor and the law hasn't changed then it will probably end up 50-50.