I was driving behind an audi s6 (one of the newer models with full led lighting) at night. i found its led brake lights blindingly bright. the driving lights are very bright by themselves, but they're borderline tolerable, however brake lights when they come on are extremely bright - i could not look at that car when driving behind it, it was too painful to look at. i had to take my eyes off that car and off the road ahead of me as a result of this for extended periods of time. i could not have those taillights within my field of vision, they hurt even when i tried to look away from that audi. i do not feel safe driving behind new audis and other cars that use extremely bright led taillights. i could have crashed because when i was slowing down behind that audi that lit up its taillights when braking i could not look ahead on the road and at the car. i had to brake blindly while briefly looking up for a millisecond or two (and suffering eye pain) now and then to ensure i wasn't going to crash into it. i was not able to constantly maintain the audi in front of me within field of sight due to severe eye pain it caused me. is there a law that mandates a safe light output by the headlights? because i find led taillights in general painfully bright to varying degree amongst different carmakers, with audi having the most severely painful brightness (similar to looking at the sun). *tr