According to some recent research, it appears that they do. As reported by CBS News, as speed limits have increased in recent years, more fatal car accidents have occurred. It is only logical to assume that the faster you are traveling when you get into an accident, the more severe the crash will be.
Prior to 1995, the maximum speed limit allowed by the federal government was 55 miles per hour. That number was repealed and as a result, speed limits around the country have increased ever since. The current highest speed limit in America can be found in parts of Texas and is a whopping 85 miles per hour. You may also encounter speed limits of at least 80 miles per hour in six other states in addition to Texas.
It was found that fatalities rose by four percent for every file miles per hour the speed limit was increased. That number doubled to eight percent on highways. Over a 20 year period, increased speed limits have been responsible for at least 33,000 deaths.
However, it was also found to be true that you will be safer on roads where the speed limit is approximate to the natural flow of traffic in that area. This means that on certain roads, you may be better off maintaining a speed that is consistent with the cars around you even if that entails going faster than the posted speed limit. Overall, when the flow of traffic is considered in conjunction with an increase in speed limit, fatality rates have gone down.