I think that's how it works in the UK. When the lidar detector catches you speeding it fires off a camera that takes 2 photos of the vehicle a set time apart. T

I think that's how it works in the UK. When the lidar detector catches you speeding it fires off a camera that takes 2 photos of the vehicle a set time apart. The car's progress is manually compared against a gauge painted on the road surface to see if you travelled far enough in the time between the 2 photos to have been speeding. This catches those times when a lidar detector gives a false positive.