In the USA traffic rules are often rules to generate revenue for the government and don't have a thing to do with safety Original Article Facts missing on speed limits Feb. 18, 2006 12:00 AM The recent comments in your newspaper about photo enforcement of speeding are once again missing something: facts. I have an engineering degree and have extensively researched speed limits. Here are some facts: Speed limits are almost always set incorrectly and too low. The public has heard the "speed kills" propaganda so long that they now repeat it back. If speed kills, why do European roads with higher limits have lower accident rates? Traffic engineers have scientifically determined for decades that the safest speed limit is the 85th percentile. Yet almost all speed limits are set lower, sometimes much lower than this. This provides revenue to the photo radar companies, insurance companies, and of course the cities. If slower is safer, why have accident rates been dropping since the national 55 mph speed limit was repealed years ago? Richard Clewis Tempe, Arizona