You know how some cars go down the highway and cause a cloud of smoke and you can't see a d a m n thing infront of you. How about that for our cars. Get a glycol based solution to do the same for red light cameras or maybe even speed cameras. When the picture snaps nothing but white fog is shown. If you can generate enough smog you might even be able to even dirty out the lenses on the cams. Have the fog generator or pipes sit close to the license plate area to ensure that's fogged over the most.