Estimating Your Speed? Three Ways in Washington

Posted Thursday, March 2, 2017 by Andrew Charles Huff

Police officers wanting to determine your speed have three valid methods recognized in our state by courts. They are 1) Speed Measuring Device (radar or laser) 2) Pace Method and 3) Aircraft.

The most popular method is the use of a “speed measuring device” or radar/laser gun. We have all observed a state trooper along the side of the road pointing a device at traffic to determine a vehicle’s speed. A beam is emitted from this device, bounces off the target vehicle, then returns to the device where the data is quantified into a specific reading.

The second way is the “pace” method, where an officer essentially uses their patrol vehicle to estimate another vehicle speed. An officer maintains an equal distance between the suspect car and patrol vehicle and uses the car’s speedometer to determine the vehicle speed.

The final method is the use of law enforcement aircraft and hash marks on the roadway. Here, a pilot for the Washington State Patrol will spot a vehicle that appears to be speeding, then measure the time it takes that vehicle to travel between two pre-measured hash marks on the freeway. Based on this measured time, the aircraft pilot can calculate the vehicle’s speed. The pilot next communicates this data down to a state trooper who will conduct the traffic stop.