The setting of speed limits on streets and highways is a technical science backed by many years of research and experience on what works and doesn t work for the safety and benefit of drivers. We at the Washington State Department of Transportation are often approached by citizens who feel that a change in the posted speed limit is the answer to a safety problem on a specific highway. Safety is the highest concern in any project we undertake, however changing the posted speed limit is not always the answer.
Safety is always a factor.
But the setting of speed limits is, for completely practical reasons, more fundamentally influenced by some basic principles of human behavior. The normally careful and competent actions of a reasonable person should be considered legal. Laws are established for the protection of the public and the regulation of unreasonable behavior of a few individuals. Laws cannot be effectively enforced without the consent and voluntary compliance of the majority. Research and experience have shown that effective speed limits are those that the majority of motorists naturally drive, and that raising and lowering posted speed limits doesn t substantially influence that speed.