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Can you challenge radar gun evidence in court?

On Behalf of | Jul 25, 2019 | Traffic Offenses Blog Post |

Few things may make your heart beat faster than getting pulled over by the police officer who announces, “I got you on radar doing ___ miles over the speed limit.” (Fill in your own blank.) Then the officer writes you a speeding ticket, or worse, a criminal charge for reckless driving by speed.

Should you pay the ticket and suffer the demerit points on your license and the hike in your car insurance premium?[1] Or should you hire a defense attorney to do something about it?

Drivers often wonder whether the police accurately measured how fast their car was going. Traffic police usually measure a driver’s speed in one of three ways: (1) RADAR gun, (2) LIDAR gun, or (3) pacing the motorist’s vehicle (matching the motorist’s speed and looking at the speedometer of the police car).

In court, if the ticketed driver or a defense attorney question the accuracy of the alleged speed, the government must prove that the device used by the officer was reliable. Under Virginia Code § 46.2-882, a certificate is admissible to show that police car’s speedometer, the officer’s LIDAR gun, or the tuning forks (see below) used to test the officer’s RADAR gun had been calibrated or found accurate within 6 months prior to the ticket.

If the [1] officer has this certificate of calibrations and [2] can identify the device referenced therein as what he used to measure the driver’s speed (“Officer, there are sixteen tuning forks listed on this Certificate. How do you know which ones you used prior to stopping my client?”), the judge will almost always find the evidence sufficient to convict for the speeding. In spite of this, a good traffic attorney can often still get the ticket reduced or dismissed for others reasons (e.g., the defendant has a good driving record, has done or would do a Driver Improve Class or community service, etc.)

Of course, if the officer does not have the certificate of calibration or it is more than 6 months old, the judge is likely to dismiss the ticket.

Note that when the officer relied on RADAR, proving he or she accurately clocked a motorist’s speed is a two-step process. The certificate of calibration (step 1) only shows that the officer’s two tuning forks resonated at known frequencies. For example, a police department issues 35 mph and 65 mph tuning forks to each traffic officer. When struck against a wooden block, these tunings forks oscillate at 2542.0 and 4736.00 cycles per second, respectively. At the beginning of his or her shift, the officer must check the RADAR antenna using these tuning forks (step 2). When the officer points the RADAR antenna at each ringing tuning fork, the display should then read 35 mph or 65 mph, respectively.

If the officer did not check his or her RADAR’s accuracy on the day of the ticket, or the RADAR did not show the expected mph when tested on the tuning forks, the RADAR was not working properly. In either situation, the ticket should be dismissed.

[1] On top of demerit points and more expensive insurance, if you face a Reckless Driving by Speed charge under Virginia Code § 46.2-862, you could go to jail for up to 12 months, be fined up to $2500.00, and lose your license for 6 months.