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You are driving on I 287 in Greenburgh, New York, when you are stopped by a New York State Trooper who issues you a ticket for speeding. At a subsequent conference, for whatever reason, you (or your attorney) are unable to reach an agreement with the prosecutor on a plea bargain and your case is scheduled for trial.

At trial, your lawyer argues that the Trooper has not produced sufficient proof establishing that the radar unit he used to determine the speed of your vehicle was in proper working order. The judge agrees with your attorney and excludes all radar evidence from your trial. You win, right? Without any radar evidence or evidence that the Trooper paced your vehicle, how can the prosecution prove you were speeding beyond a reasonable doubt? Case over – not guilty. Wrong.

In New York, like many other states, you can be convicted of speeding based solely on the officer’s visual estimate of the speed of your vehicle, uncorroborated by devices such as radar or laser. People v. Olsen, 22 N.Y.2d 230 (1968). Prior to the Olsen decision, such visual estimate opinion evidence alone however, was insufficient for conviction. People v. Magri, 3 N.Y.2d 562 (1958).

In Magri, the accuracy of the radar equipment used to measure the defendant’s speed was not proven. For that reason, the Court held that the radar evidence of Magri’s speed was, without more, insufficient proof of the speeding charge. However, the Court upheld Magri’s conviction anyway since there was additional competent proof in “the testimony of the two qualified and experienced police officers, who had adequate opportunity to observe defendant’s vehicle as it approached the radar car.” Id at 367. In other words, Magri established that the prosecution need not establish that the radar, laser, speedometer or other speed measuring device was in proper working order if there is opinion testimony from a qualified officer as to defendant’s speed corroborating the reading on the speed measuring device.
Under the holding in Magri, at least there had to be more than just an officer’s “radar eyes” visual estimate testimony. The officer’s visual estimate had to be corroborated by a speed measuring device such as laser or radar. That all changed June 5, 1968 when the Court of Appeal decided People v. Olsen.

In Olsen, the defendant was convicted of speeding but an appellate court reversed the conviction. Id at 231. As explained below, the New York Court of Appeals ultimately reversed the appellate court and reinstated the conviction.
The only evidence that defendant operated his vehicle in excess of the 30 m.p.h. speed limit was the uncorroborated testimony of two police officers that they had observed defendant’s vehicle and estimated its speed to be between 50 and 55 In reversing the conviction, the appellate court held that the officer’s visual estimate “testimony, uncorroborated by any mechanical device for gauging speed, was insufficient, as a matter of law, to sustain the defendant’s conviction.” Id at 231.

The appellate court’s reversal was appealed to the Court of Appeals which framed the issue as “whether the opinion evidence of police officers, properly qualified to testify as experts, is sufficient to sustain a conviction for speeding.” Id. The Court noted that heretofore, police testimony had to be corroborated by some mechanical device. Id.

Recall, the appellate court had held that an officer’s uncorroborated opinion testimony as to a vehicle’s speed based upon that officer’s observation of said vehicle is insufficient as a matter of law. The Court of Appeals disagreed citing to several civil cases establishing “that opinion evidence with regard to the speed of moving vehicles is admissible provided that the witness who testifies first shows some experience in observing the rate of speed of moving objects or some other satisfactory reason or basis for his opinion.” Id at 232.

The Court did concede “that a police officer cannot testify with precise accuracy as to speed of a vehicle.” However, the Court “fail[ed] to perceive any reason why [opinion evidence regarding vehicle speed] should be held to be insufficient as a matter of law to sustain a conviction for speeding in every case.” Id (emphasis in original). Estimates of a vehicle’s speed, based upon considerable experience, “must not be ignored in all cases.” Id. In Olsen, the officers estimated that the defendant was traveling between 50 and 55 m.p.h. in a 30 m.p.h. zone. That should have been, held the Court, sufficient to sustain a conviction. Id.

To its credit, the Court addressed the obvious observing that an officer’s estimate “absent mechanical corroboration, that a vehicle was proceeding at 35 or 40 miles per hour in [a 30 m.p.h.] zone might for obvious reason be insufficient, since it may be assumed that only a mechanical device could detect such a slight variance with accuracy sufficient to satisfy the burden necessary to sustain a conviction.” Id.

To summarize: Olsen established:
(1) that the uncorroborated opinion of a trained officer with regard to a vehicle’s speed might be sufficient to sustain a conviction for speeding;
(2) that the variance between the officer’s estimated speed and the posted speed limit must be sufficiently wide so that we may be certain beyond a reasonable doubt that the defendant exceeded the permissible limit;
(3) it may be difficult in a particular case to determine whether the variance between the estimated speed and maximum permissible speed is sufficiently wide;
(4) that the court must consider the facts and circumstances of the case including the nature and extent of the opportunity which the officer had to view the moving vehicle.
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