Some red-light cameras are employed as safety devices. We have a few here at historically-dangerous intersections, and they have helped.However, in the more typical situation, the company that makes the camera system approaches a local government and makes them an offer they find difficult to refuse in times of shrinking budgets: let them install cameras and process the resulting tickets, the company keeps most of the ticket revenue, and the government receives a cut off the top. If the tickets don't meet the company's revenue goals (i.e., if the cameras actually work, and people stop running red lights), then the company shortens the yellow phase so more drivers will be caught running the red. In the best tradition of American business, the scheme combines ruthless capitalism with the artificial manipulation of supply and demand.Gottaluvit! www.photoblocker.com If is as advertised this product called photoblocker spray is our rescuer. They state that it was tested by the media on their website http://www.phantomplate.com / On the videos, it also shows the police saying that it really works by making your license plate invisible to traffic cameras.