Jaff
I think he can go anywhere in the EEC with a British passport and no Visa, which gives quite a lot of scope.

Assuming of course he wasn't made to surrender his passport pending trial, it may be that hs is suject to questioning on exit as I'm sure there will be a note on his passport record in case he tried to leave the country with no intention of returning. I'm only surmising this is hot the system works.