I used to work in the automotive lighting world.
Actually, it's a FEDERAL motor vehicle safety statute (FMVSS) that governs vehicle lighting colors.
And the reason blue dots are illegal isn't really about people confusing your old pickup with a police car. It's all about reaction times. Since first introduced, brake light color has been restricted to a certain range. (Originally, it was the range of red within which the glass staining process could be controlled at the manufacturer.)
Even with the switch to plastic lenses on incandescent lamps, and now LEDs, we're still using that same color range, because our brains are conditioned to recognize that specific color as brake lights. When we see bright lights of a different color, it takes longer for us to process that, recognize it as a brake light, and react appropriately.
Sure, purple lights from blue dot lenses wouldn't slow our brains down much... But at 80mph, a TENTH of a second is TWELVE FEET further you've travelled before hitting the brakes. Don't know about you, but the guy behind me rarely leaves an EXTRA twelve feet of cushion between us. (Unless I *really* have my foot in the throttle that day...)
Yes, enforcement varies wildly. By state, and even by county or town. And they DO look cool. Just think about the reason for the rule, whether your local enforcement has time to worry about this (or other reasons to hassle *you*), and how you use your truck.
Cheers,
mark.
'51 KY 3100
