it was tried here in hawaii a few years ago. speed cams got tossed after less than a year in operation. planned red light cams didn't even see the light of day.
a private firm was contracted to nab speeders from vans parked around blind curves, bushes, etc. they were immediatly accused of "shaving" the allowable 5-10 mph over the speed limit that our city police "unofficially" lets drivers get away with down to below 5 mph as a way to increase profits. a local traffic court judge agreed that shaving was occurring and proceeded to toss out all citations that showed less than 10 mph over the limit. the city and state lawmakers that wanted to ram this program through circled their wagons and got indignant and arrogant because the public couldn't see things their way.
the driving public demanded from these lawmakers to know just how much over the speed limit was allowed, and the hold-out lawmakers balked, which made the public even more suspicious of a scam.
lines were drawn amongst the driving public with a small minority supporting the program. their justification for keeping the program was that speed limits should be strictly enforced to reduce traffic accidents and fatalities. these drivers were accused of being the very ones that created hazardous driving conditions by plugging up the fast lanes and forcing drivers to use risky and dangerous manuevers to get around them.
it didn't help that hawaii traffic law is vague on whether or not the far left lane on a freeway is a passing lane or not.
there were incidences of irate drivers confronting the lazer gun operaters in their vans, especially in remote areas, and especially at night.
a rather loud argument that state and city lawmakers only sponsored this program as a way of padding its coffers was a constant and grating reminder to hawaii's driving public that this whole program was just a scam perpetrated by some government insiders and the company running the operation.
under unrelenting public pressure the whole mess came to a screeching halt. the state and city lawmakers that refused to budge finally caved in and paid a political price for their efforts. although amazingly, during the next and following legislative sessions some die-hard proponents tried to revive it.