Abstract
No single method will minimize the deaths and injuries that result from motor vehicle crashes. Countermeasures must be applied that not only reduce the incident of crashes but also reduce the damage that results excessive speed is undeniably a major contributing factor to crash losses. Speed control is therefore a vital part of efforts to assure the safety of all highway users. Radar can control that speed. But in several U.S. states the use of radar in speed detection is prohibited. This paper reviews these prohibitions.