A police officer once told me his favorite traffic ticket to write was "excessive visible emission". I've noticed a difference in the approach to enforcement o

A police officer once told me his favorite traffic ticket to write was "excessive visible emission". I've noticed a difference in the approach to enforcement of many minor regulations between the US and Germany, where I've spend a considerable amount of time. In the US, it's common for things like vehicle emissions and safety to be subject to many regulations, but only checked if somebody complains or the police happen to notice. In Germany, cars are regularly subjected to fairly strict inspections. So people in the US do a lot of things with their cars that aren't technically legal. For the most part, this doesn't seem to be a major safety issue. In an analysis by the Department of Transportation[0], 4.9% of crashes were found to involve a tire/wheel deficiency and 1.9% involved some other vehicle deficiency. Tire pressure monitoring recently became mandatory on new cars sold in the US, which should have a significant impact on the most common maintenance issue. It's likely that a comprehensive vehicle inspection program would not have a particularly good cost/benefit ratio relative to, for example improving traffic flow and signaling at intersections. 36.2% of crashes involved intersections. [0] https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/811059 https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/...