Speed Measuring Devices Used By Police

Radar (Radio Detection and Ranging):

A police speed radar gun is recognized by the courts as an accurate form of clocking a moving vehicle’s speed. A simple explanation of how a radar gun works is that it sends out radio waves of specific frequencies which bounce off of moving vehicles which then return to the radar device. When these radio waves are reflected off of a moving vehicle, a measurable frequency shift, called Doppler Shift, occurs which is used to calculate the moving speed of the vehicle.

There are two types of speed radar devices: Stationary Radar and Moving Radar. The Stationary Radar is used while the officer and the radar device are in a fixed position, clocking the speed of a moving vehicle. This is the device used when an officer is on the side of the street or parked in a car on radar duty. The Moving Radar is used in a moving police car and is calibrated to be able to factor in the speed of the moving police car. This means that if the police car is moving at 50km/hr and the radar detects that the moving vehicle is moving away at 30km/hr, the speed of the moving vehicle will be 80km/hr.

Speed radar devices are considered very accurate, if the officer using the device has the proper training and experience to use the radar. The range of a radar unit is approximately up to 300 metres, but different factors can affect this range from the time of day, to the weather. Hiring the professionals at Traffic Ticket Solutions means getting a paralegal on your side that knows exactly what training is sufficient for the officer to have the proper working knowledge of the specific radar device used that clocked your vehicle. We also know what sort of factors can influence a radar reading and know where to look for any influencing factors that could help to win your radar speeding ticket case.

Laser (Light Amplification by Simulated Emission of Radiation):

A police speed laser gun is recognized by the courts as an accurate form of clocking a moving vehicle’s speed. Unlike the radar that uses radio waves, a laser uses a short burst of light energy to calculate the speed of a moving vehicle. The laser also differs from a radar because the officer has an actual eyepiece to target a specific vehicle by moving the laser gun until a red dot is present at the front of the moving target. The officer then pulls the trigger on the laser speed gun which sends out a short burst of infrared laser light which bounces off the moving vehicle and reflects back to the speed laser device. The laser gun counts the number of nanoseconds it takes for the laser light to return, and then can calculate the distance to the car. If the gun takes 1,000 samples per second, it can compare the change in distance between samples and calculate the speed of the moving vehicle. The speed laser device is more accurate with less chance of misinterpretation over the older radar devices. If an officer gave you a speeding ticket while using a laser device, you will need the help of a professional to be able to properly analyze the disclosure and qualifications of the officer to use that device.


Pacing is recognized by the courts as an accurate form of clocking the speed of a moving vehicle. Unlike the Radar and Laser devices, pacing does not involve any sort of speed device to measure the rate of speed that your car is traveling. Believe it or not, pacing is one of the more accurate forms of measuring the speed of a moving vehicle and one of the most difficult to contest in court. Pacing involves an officer following a moving vehicle until he is moving at the same speed as the vehicle he is following for a specific amount of time. He then records the speed that is registered on his speedometer. Proper tests and proof of proper working order are needed to prove that the officer’s speedometer was able to give a proper reading at the time of the incident and a professional from Traffic Ticket Solutions will know exactly what to look for in the officer’s disclosure to help build a defence for your speed pacing case.