Law enforcement officers use different methods to measure drivers’ speeds. If you received a speeding ticket, it may not be obvious to you which method the officer used to measure your speed. We all have seen officers on the side of a road pointing a speed measuring device at passing cars. But a hand-held device is not the only way law enforcement measure drivers’ speeds when issuing speeding tickets.
In this article we will list the methods that officers use to measure drivers’ speeds. In addition, we will go into some detail about each speed measuring method.
HOW COPS MEASURE SPEED IN WASHINGTON STATE: INTRODUCTION
In Washington State, law enforcement officers use several methods to measure drivers’ speeds. We will discuss 4 of the most common methods. They are:
HOW COPS MEASURE SPEED IN WASHINGTON STATE: RADAR
RADAR stands for Radio Detection And Ranging. RADAR uses radio waves to measure distance of objects by transmitting and receiving radio waves. It generates radio waves with a transmitter. When the waves bounce back off the object, they are picked up by the receiver and analyzed. The change in distance of the object with respect to time will determine the object’s speed.
Read more about RADAR units.
HOW COPS MEASURE SPEED IN WASHINGTON STATE: LIDAR
LIDAR looks and acts like a hand-held radar gun. It works by bouncing a beam of laser off target vehicles. The distance between the unit and the target vehicle and the time it takes the beam to return to the laser gun after bouncing off the target vehicle allows it to calculate the speed of the target vehicle.
If your speeding ticket involves a LIDAR unit, please click here to read more about LIDAR units.
HOW COPS MEASURE SPEED IN WASHINGTON STATE: PACING
Pacing is when the officer follows a suspect’s vehicle and uses his or her own speedometer to measure the speed of the suspect’s vehicle. The officer must maintain a constant distance between the his or her own vehicle and the target vehicle long enough to accurately estimate the target vehicle’s speed.
If your speeding ticket involves pacing, please click here to read more about pacing.
HOW COPS MEASURE SPEED IN WASHINGTON STATE: ASD
ASD stands for Aircraft Speed Detection. This method of measuring speed is not very common in Washington State. However, the way it works is an officer in an aircraft estimates the speed of the target vehicle. He or she then radios a waiting ground patrol officer who issues a ticket to the driver.
There are two ways officer measure drivers’ speeds in aircraft cases. First method is similar to the pacing method described above. Second method is where the officers use two highway markings at a premeasured distance apart. They then calculate the target vehicle’s speed by timing how long it takes the vehicle to pass between the two highway markings.
If your speeding ticket involves aircraft speed detection, please click here to read more about it.
Greg Sarkisyan is an attorney at Community Law Firm, PLLC, and the author of this post. If you would like to read more, visit us here. If you need legal assistance call (206) 262-7390 or e-mail Help@CommunityLawPLLC.com.