i think they're kept for a few years. i often have to clean the cctv room and get to see behind the scenes its well cool. all the police in there talking to each other tracking people on the cameras even if its normal old joe bloggs, whenever you walk past a cctv camera they talk about you and say if you look dodgy and where you are heading. theres like thousands of tapes all categeriseed in there too. so i always wave when walking past the cameras now
