In The People of the State of New York v. Kahan , Michael Kahan was convicted of speeding by a Justice Court Judge of the Town of Deerpark (Orange County).
Kahan was allegedly clocked traveling at 51 miles per hour in a 30 mile per hour zone, but challenged the accuracy of the speed recorded by the officer's radar device. During the non-jury trial, the judge dertermined that Kahan had the "burden" of establishing that the results were inaccurate or that the device was not in working order.
On appeal, the Appellate Term, 9th and 10th Judicial Districts, found that the trial court erred.
According to scientific analysis, when a radar device is used within a moving vehicle there is a high probability of signal distortion or error. Additionally, when there is heavy traffic or obstructions (like large trucks, billboards or other roadside objects), an officer must take measures to ensure that those impediments are not triggering signal interference or a misidentification.
Because of the great potential for error, the AT concluded that the government bears the responsibility of establishing that the device accurately recorded a driver's speed. To that end, a prosecutor is required to elicit testimony at trial that the radar "was in the proper working condition and that it was operated correctly by one who was qualified and experienced in the operation of traffic radar," and that the "police officer independently verified the speed of the patrol vehicle (e.g., by comparing the speed registered by the radar unit with the speed indicated by the patrol vehicle speedometer), and that the radar was used in an area posing a minimal risk of misidentification or distortion ...."
In this particular instance, since the appellate court was unable to find testimony that satisfied those standards, the underlying evidence was deemed "legally insufficient," the conviction was reversed, and, the case was dismissed.

Was that good lawyering or good luck? (Your call!)
For a copy of the Appellate Term's decision, please use this link: The People of the State of New York v. Kahan