In State v Dantonio, the New Jersey Supreme Court held that the evidence of radar speed meter readings should be received into evidence upon a showing that the radar was properly set up and tested by the police officer. Similarly, the Appellate Division held in State v Wojtkowiak that the K-55 radar device is completely reliable as a speed measuring device. Likewise, laser radar devices and Vascar have also been accepted by the courts as being scientifically reliable.
HOWEVER, the scientific reliability of the radar device is only one part of the proofs the state must offer during trial for the radar speed reading to be admitted into evidence. In addition to proving the reliability of the device, the state must prove that the device wasproperly calibrated and operated by a trained and experienced police operator.
For example, in connection with the K-55 radar instrument, the state should adduce evidence as to the specific training and extent of experience of the police officer operating the radar, the calibration of the machine prior to stopping the defendant through the use of tuning forks, which should also be independently calibrated, and the calibration of the speedometer in the patrol car if the K-55 is operated in moving mode.
Although the proofs necessary for admissibility are similar with laser radar units, there are some slight differences. However, evidence of calibration is still required. In addition, should the radar be employed during a period of snow or heavy rain, the state may be required to introduce expert testimony as to the reliability of the instrument. Moreover, the state must elicit proof that the officer performed the pre-operational procedures as recommended by the manufacturer prior to use. In most instances, testimony and documents pertaining to the testing and accuracy of the radar prior to and after the police officer’s shift may be introduced, similar to all speeding ticket prosecutions.
Basically, the state must prove that the officer was qualified to operated the radar, that the radar was in proper working order, and that is is the type of radar that has been accepted as scientifically reliable without the need for expert testimony.
This is a simple summary, but practical nonetheless. I can be contacted for more information on fighting New Jersey speeding ticket