“Roadway design and use should be part of every speed setting discussion, and debate about speed limits should distinguish between speed causing a crash, and speed influencing injury severity once a crash occurs. Safety statistics vary greatly according to roadway class. Ironically, local roads, which normally have the lowest posted speed limits, have the highest fatality rate of any roadways.”

The Office of Highway Safety, Federal Highway Administration, US Department of Transportation


“Current speed limits are set too low to be accepted as reasonable by the vast majority of drivers. Only about 1 in 10 speed zones has better than 50-percent compliance. The posted speeds make technical violators out of motorists driving at reasonable and safe speeds.

For the traffic law system to minimize accident risk, then speed limits need to be properly set to define maximum safe speed. Our studies show that most speed zones are posted 8 to 12 mph below the prevailing travel speed and 15 mph or more below the maximum safe speed. Increasing speed limits to more realistic levels will not result in higher speeds but would increase voluntary compliance and target enforcement at the occasional violator and high-risk driver.”

Samuel C. Tignor, Ph.D., and Davey Warren, Traffic Safety Research Division of the Federal Highway Administration in McLean, Virginia


Important facts obtained from the National Center for Policy Analysis and Iowa Highway Safety Management System:

  • Before the speed limit in Iowa increased to 65 mph an average of 71 percent of the motoring public were exceeding the speed limit. After increasing the speed limit, that number fell significantly to 31.2 percent. National data shows that the closer the posted speed is to the speed motorists deem “reasonable,” the more likely they are to abide by the speed limit.
  • The “85th percentile” is a common statistic used by traffic engineers to study travel speeds. The “85th percentile” is the speed 85 percent of motorists drive and is considered to be a reasonable and safe speed. In Iowa, the speed that coincides with the “85th percentile” is 70 mph, which represents the natural flow of traffic, regardless of posted limits.
  • By increasing the speed limit to 70 mph, it will actually reduce the speed differentials between passenger vehicles. This reduction in speed differentials will greatly improve the efficiency and safety of interstate roads.

Jeff Ogden, the president of AAA Minnesota/Iowa


Seven Major Myths of Speed and Speed Enforcement:

  • Speed Is a Major Cause of Accidents and Fatalities
  • Speed Enforcement Increases Safety
  • Slower Is Always Safer
  • Use of Radar Detectors Increases Speeds and Accidents
  • The Federal 55-mph Limit Saved Thousands of Lives
  • Speed Enforcement is Driven by Safety Concern
  • Lower Speed Limits Reduce Average Speeds and Accidents

Gary Witzenburg, Consumer Guide


Since most citizens can be relied upon to behave in a reasonable manner as they go about their daily activities, many of our laws reflect observations of the way reasonable people behave under most circumstances. Traffic regulations are invariably based upon observations of the behavior of groups of travelers under various conditions.

Generally speaking, traffic laws that reflect the behavior of the majority of vehicle operators are found to be successful, while laws that arbitrarily restrict the majority of drivers encourage wholesale violations, lack public support, and usually fail to bring about desirable changes in driving behavior. This is especially true of speed zoning.

Arizona Department of Transportation


Will a lower speed limit slow traffic down?

The Myth…
It is a common myth that posting slower speed limit signs forces drivers to slow down and will result in fewer traffic accidents. National research has shown that drivers are influenced by the prevailing traffic conditions and the type of street, not the posted speed limit.

The official Web site of the town of Gilbert, Arizona


Q: What effect do posted speed limits have on actual speeds?

A: Before and after studies consistently demonstrate that there are no significant changes in traffic speeds following the posting of new speed limit signs. Tests done by the TMAC (Traffic Management Advisory Committee) and the Police Department show that the vast majority Needham motorists drive at 30 mph or less, and that the observer tend to overestimate the speed of passing cars.

The official Web site of Town of Needham, Massachusetts


“The status of traffic law observance in any community is definitely related to a number of … factors. Important among these factors are:

  1. Reasonableness of traffic rules and regulations. It is well known that good observance can only be expected for regulations which are generally deemed sensible, necessary and reasonable. They should also be as simple and as few in number as possible. The Uniform Vehicle Code and the Model Traffic Ordinance constitute valuable guides to states and municipalities in setting up reasonable regulations.
  2. Effective and sensible signs, signals and markings, wisely used.
  3. Adequate public understanding and appreciation of traffic regulations, of the reasons for them, of the results to be accomplished, and of methods of proper observance.
  4. Uniform, impartial and business-like enforcement.

To enforce traffic laws is to compel obedience of them. The fact that so much compulsion seems necessary is a clear indication of serious deficiency in one or more of the first three factors presented above. Thus, although enforcement should only be necessary for a small perverse minority, it is all too much invoked for large proportions … The really needed steps to reduce violations are the effective promulgation of reasonable regulations and the education of the public as to the saneness, necessity and value of them and as to how the individual is expected to act in compliance with the said laws.”

Publication No. FHWA-RD-89-103: Motorist Compliance With Standard Traffic Control Devices
US Department of Transportation, Federal Highway Administration


JULIE CIRILLO, the program manager at the FHWA Office of Motor Carriers and Highway Safety, said:

” . . . the more you have differential speed the more you have accidents.

. . . we have fallen into a situation where for a variety of reasons we are setting speed limits that are not realistic. They are setting speed limits that are too low. We’re legislating them, and once you legislate speed limits, invariably the speed limit is at about the 50th percentile. So, here you have a traffic regulation that’s enforceable by law and half of the people are exceeding it when you put it in place. That makes no sense to us. So, what we’re trying to do is get the states to agree that they will st speed limits in accordance with the 85th percentile, which is where most people travel. Most people are sane. Most people wil not put themselves in udue hazard. . . .

. . . We have deteriorated the value of speed limits and now find the disregard for speed limits is spilling over into other traffic-control devices — disregard of red lights, disregard of stop signs. If we have any hope of moving the population back to where it ought to be, we have to set reasonable speed limits.”

June/July, 1999 issue of LANDLINE, the magazine of OOIDA (Owner-Operator Independent Drivers Association)


Now here is the good news. Since 1995 when the speed limits were raised to 75 and 80 mph in some states, the death rate on the highways has fallen dramatically. It has not risen. The injury rate has fallen too. It turns out the 6,400 additional deaths prediction was a complete fabrication. The 40 states that have raised their speed limits to 65 or above have not seen much difference at all in their injury rates from those states that kept their speed limits at 55. The nation’s roads and highways are “safer than ever” proclaims the National Highway Traffic Safety Administration.

The Nader groups, you might think would now be forced to eat some crow and admit that they were spreading lies when they claimed a big loss of life from higher speed limits. No. Now they say that what they had predicted was “as many as 6,400 added deaths.” Well, I guess, zero is technically “as many as 6,400.” But of course, that is like saying that I might hit as many as 75 homeruns in the major leagues this year.

One last point: Imagine for a moment that the death rate had spiked up this year and in previous years. You can bet that Ralph Nader and Joan Claybrook would be on every TV talk show pontificating about how Republicans in Congress have blood on their hands. Instead, when the improved traffic safety numbers were released, almost no major media outlet made notice. Few if any called the safety groups to task for their false doom and gloom predictions. The media seems as embarrassed by the recent good news on traffic safety as the Nader groups are.

Stephen Moore in National Review On-Line, 6/03


Every year, over 3-million Americans will die from various causes. Only 1% will die in motor vehicle crashes. You are 8,000 times more likely to die from medical malpractice than from speeding. You are three times more likely to die from heart attack or stroke from routine physical exercise during traditional sporting events, especially basketball, swimming and football. You are more likely to be murdered than to die in a car crash. Most fatal “accidents” occur in the home – no speeding required.

The American Autobahn by Mark Rask


“I realized that a country in which virtually every citizen drives over the speed limit is impossible to lead by government direction.”

Newt Gingrich, Former Speaker of the House