Now they have a new weapon in their arsenal, and it comes in a can for $29.99. A clear spray called PhotoBlockerTM can be applied to license plates to make them hyper-reflective and unreadable when the camera flashes

Fuzzing up the policing picture A licenseplate spray thwarts cameras set up to catch drivers running red lights. But what of safety and the law?

On a perfectly clear day in October, Carla Correa drove her Honda Civic toward an intersection in Baltimore. When the light turned yellow, she did not cruise through. She hit the brakes. Seconds later, a truck rammed her from behind, and her car was wrecked. Why would she do such a thing? The answer could be found in a box mounted on a nearby post, with a lens pointed at her license plate

it will hide your license plate from red light cameras…

License-plate spray foils traffic cameras”
Washington Times

a hit with drivers

…beats traffic camera tickets in a flash

“The Denver Police Department … conducted a road test two years ago and found that PhotoBlocker was effective . . . Similar results were found by 
TV news.