No, you cannot be prosecuted on a forward-facing Gatso (source, staff at a Safety Partnership). If lines across road are on both sides of camera, camera will be reversible. The Gatso housing must be decorated with day-glo striping, I believe, and this only appears on the back, as you are approaching it in the vulnerable position. All the Gatsos I know (Scottish Borders) are set to ACPO recommendations, eg 10% + 2 mph. That means they only fire at 68 in a 60 limit. IF you have a very accurate speedometer (such as a satelite GPS unit) you can prove this for yourself! In fact, you will be well past the camera by the time the second flash takes place. QED.