Radar has been used by law enforcement agencies to enforce vehicular speeding regulations for nearly 30 years. During this time, the scientific reliability and accuracy of police radar devices have generally been accepted by the courts and the public. Recently, however, as radar technology has become more complex, the scientific reliability and accuracy of radar devices have been challenged. Consequently, the State courts have adopted conflicting views concerning the effect of radar reliability and accuracy on the admissibility and weight of radar evidence in speeding violation cases. Until a radar device is invented that is accurate under any conditions, fairness dictates that contested prosecutions be conducted according to meaningful standards which ensure the instrument's accuracy. Guidelines for the admissibility of radar evidence should require the prosecution to show that the radar instrument used in the case was operating reliably and accurately at the time and under the circumstances of the alleged offense and that it was being operated by an officer trained in its use. A total of 173 footnotes are provided.