Sneak behind it and smash it with a baseball bat. If they suspect you or fight back - they are the ones not roleplaying. Speed cameras are only designed to catch speeders, not assaulters.. Cameras can't fight back either.
Either way.. I don't see WHY you would NEED to be a camera. Most cops nowadays have radar guns that do not need a cord. It's portable. So have a partner with a patrol car ready and hidden, hide in the woods or an alley or something. Calibrate the speed of every car that appears to be speeding. If they're speeding, suspect them, and radio your partner to go after them.
That's how cops set up 'speed traps' sometimes. I saw it on a reality TV show.