Law enforcement agencies enforce speed limits in a variety of ways as of 2015, including handheld radar guns and photo speed devices. Officers also use a technique called pacing to identify drivers traveling over the speed limit, explains the Illinois State Police.Continue Reading
Handheld radar uses Doppler technology to calculate the speed of a moving vehicle, explains RadarTest.com. Officers typically sit stationary along a highway and point the radar gun towards oncoming traffic. Law enforcement can also mount the radar within the squad car to track speeds while driving within the traffic. Some versions of radar record speeds for drivers traveling behind an officer.
Photo radar involves a two-step process. Law enforcement agencies place fixed radar devices on specific streets, according to the Washington DC Metropolitan Police. When the radar identifies a speeding vehicle, a camera immediately photographs the back of the car. The agency uses the license plate number to identify the driver and sends a speeding ticket to the address of record.
The process of pacing requires the officer to follow or drive near a car, explains VirginiaTicketHelp.com. Upon reaching a speed comparable to the targeted car, the officer makes note of the speed on his speedometer and performs a traffic stop if applicable.Learn more about Driving Laws