Speed Reading Instruments in Maryland

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There are a few common speed reading instruments and methods that officers in Maryland use to determine the speed of a vehicle. Those include pacing, radar, and laser. Radar and LIDAR are both sophisticated methods of speed reading, but with the help of a Maryland traffic lawyer it may sometimes be possible to defend against the accuracy of these instruments and their readings, in court.

Officers come to court to show that they are trained and certified in whatever method or instrument was used to record the speed. They also demonstrate that the device used was fully operational at the time that the speed was recorded. This can be extremely difficult to overcome in court.

Maryland Speed Limit Laws

Maryland has an absolute speed limit law. If the posted speed limit is 40 miles per hour and someone drives 41 miles per hour or more, they violated the law. Even when a driver is going just one mile over the speed limit, they are guilty of speeding.

A person can be pulled over for going one to five miles over the speed limit if the officer believes that he or she is committing some other violation. For example, if an officer suspects someone of driving while intoxicated, they will pull that person over initially for driving over the speed limit so they can assess whether the person is driving while intoxicated.


In speeding cases, it is usually the driver’s word against the officer, regardless of which method was used to track the driver’s speed. There is always a possibility that someone can question the officer’s determination of their speed. In that case, they need to determine the method the officer used to figure out the person’s speed and attack that particular method. There are also defenses such as claiming an emergency forced a person to exceed the speed limit, or claiming the officer mistook the person’s car for another vehicle.

Traffic Radar Tools

Radar uses radio waves reflected off a moving object to determine its speed. That speed is shown on the instrument for the officer to read. This method of speed detection is used by Maryland law enforcement officersA radar reading has a lot of importance because it is difficult to convince a judge that a sophisticated electronic radar device is incorrect or broken and did not show the driver’s accurate speed.

An officer must come to court and show they are trained and certified to use the radar equipment. As long as that determination by the officer is met, the evidence carries a great deal of importance with all judges.

LIDAR Technology

LIDAR uses a low-powered beam of laser light that bounces off the targeted vehicle and then returns to a receiver in the unit to calculate the speed of the vehicle. These devices are supposed to be more accurate than radar units. But to be accurate, the officer must hold the beam on the same part of the car whenever he is tracking the speed. This is tricky to do because the laser beam is narrow. It is impossible for the officer to be sure that they did this correctly because they aren’t able to see the beam when they are pointing it at a vehicle. This is something that can be used as a defense when questioning the officer regarding the type of method used to determine the person’s speed.