Laws about using CCTV to issue moving traffic PCNs

[Undinist]

Anyone know where I can find authoritative info on this? I've read that the council is obliged to put up warning signs in areas where they use CCTV to issue moving traffic PCNs for offences such as illegal turns. I've also read that they have to use approved types of camera. Where can I find chapter and verse? I've had a good google but can't find much. I have a hunch that my borough, Loony Lambeth, is issuing an awful lot of dubious moving traffic PCNs which need to be challenged. Basically the whole borough is effectively full of traffic cameras, but you don't know about it until you get a PCN.