Conford, Handler and Meanor. The opinion of the Court was delivered by Conford, P.J.A.D.
Defendant challenges his conviction of driving 75.3 miles an hour in a 55 m.p.h. zone on U.S. Rt. 322 on May 5, 1973, primarily on the ground that the evidence of his guilt rests solely on a reading of his speed by a VASCAR device operated by a state trooper. The contention is that expert testimony as to the reliability of the device, which was not here presented before the trial tribunals, is an essential prerequisite for the admissibility of such evidence. The State takes the position that the scientific reliability of the device is a proper subject of judicial notice and that both the accuracy of the instrument used and the qualifications of the trooper who employed it were fully established by evidence adduced at the trial before the Municipal Court of Folsom Borough. The conviction in that court was affirmed in a trial de novo on the municipal court transcript before the Atlantic County Court.
The general reliability of the VASCAR device was held to have been established by expert proof by the Somerset County Court in State v. Schmiede, 118 N.J. Super. 576 (Cty Ct. 1972), where a conviction for a speeding offense proved by a VASCAR reading was affirmed. We arrived at the same conclusion, also by reason of the adduction of expert proof on the subject before the trial court, in State v. Salup, which is being decided simultaneously herewith. 128 N.J. Super. 209. There is no reported New Jersey case in which a conviction based on VASCAR-derived evidence has been reversed, or where VASCAR readings have been rejected as evidence, on account of the unreliability of the device.*fn1 The substantial question before us on this appeal is
whether sufficient indication of the general reliability of VASCAR is not now available to warrant the court's taking judicial notice thereof so as to dispense with the necessity in each of the scores (if not hundreds) of prosecutions annually based on use of the instrument of submitting expert proof to establish such reliability.
An understanding of the evidence in the present case and of our conclusions as to judicial notice require a description of the VASCAR device and of how it functions. The account which follows is derived from the record in State v. Salup, supra, the opinion in State v. Schmiede, supra, the testimony herein and documents hereinafter mentioned supplied the court by the State. The principles underlying VASCAR are simple. The apparatus is mounted in and powered by the battery of a motor vehicle. As the operator opens and closes a distance switch it measures the distance traversed by the vehicle during the interim and simultaneously feeds that information into a computer module. The distance is measured by an odometer module which is linked with the speedometer cable of the control car, but the measurement is not affected by the accuracy of the speedometer. The VASCAR unit also measures the period of time elapsing between the opening and closing by the operator of a time switch, and simultaneously feeds that information into the computer module. The switches can be opened and closed, as between distance and time, in any order. When both pieces of information (distance and time) have been stored in the computer there is within a second a computation by the computer module of the speed of a target vehicle, in terms of miles per hour
to the nearest one-tenth of a mile, represented by the ratio of the inputs of distance to time as fed into the computer. This figure is flashed to a screen on the apparatus visible to the operator.
The method of use of VASCAR by a police officer in detecting the speed of a target vehicle depends upon whether the clocking car is following the target car, is being followed by it, the cars are approaching each other from opposite directions, or the clocking car is parked alongside the highway while the target car passes by. VASCAR can be used in any of these situations. When both clocking and target vehicles are in motion during the maneuver the technique is as follows. The operator notes the moment when the target car passes a particular reference point, e.g., a bridge, signpost, tree, etc. To avoid problems of depth perception the shadow cast by the object is ordinarily used. At that moment the operator turns on the VASCAR time switch. When the target car passes a second reference point the time switch is turned off. The operator activates the distance measurement by turning the distance switch on and off as the clocking car passes the same two reference points.
When the clocking car is stationary, as in the instant case, it is necessary that the reference points be predetermined and that the clocking vehicle travel the course in advance, thus locking the distance traversed into the computer module before the time measurement is made. That measurement is made as the target vehicle passes from one of the reference points to the other within the observation of the operator.
Either the time or distance factor may be separately erased from the computer by depressing the appropriate button. Thus a parked police vehicle can check the speed of a succession of passing target cars with only a single distance input.
A more detailed description of the technical features of the VASCAR operation, derived from the expert testimony adduced in that case, is to be found in Judge Meredith's
opinion in State v. Schmiede, supra (118 N.J. ...