Despite all the smoke blown up our whatevers about how traffic cameras "save lives" (show me the double blind studies, please), actual evidence (such as contracts with traffic camera companies) show that traffic cameras are simply a way for municipalities to increase their cash flow without resorting to tax increases. They are also a nice niche for companies with no morals to extort people out of money under the color of law. In this way, they are much like the old speed traps (or the new license checkpoints, which I don't approve of either).
In Montgomery, Alabama, a law professor received a traffic camera ticket and decided to make a fight of it. So far, he's winning.
In North Carolina, we killed the damned things by using a state law that requires the proceeds from traffic tickets to go into the local school system coffers. When the traffic camera companies realized there would be no money in it for them and the municipalities discovered their cut had just disappeared as well, the traffic cameras were gone in no time.
Odd. If so many lives were saved, you'd think the cities would have funded them themselves, wouldn't you?