Key Takeaways from NHTSA RADAR manual: How do R.A.D.A.R Devices work?

Briefly, these devices use specific characteristics of radio energy to measure speed. Built on technology developed in the late 1800’s, radar devices basically work by bouncing radio waves off of objects. The relative motion can be interpreted as speed, and can be applied to multiple situations, including traffic tickets.

For traffic purposes, there are three types of recognized “relative motion” :

1. Radar device stands still and the vehicle moves
2. Radar device moves and the vehicle stands still
3. Both the radar device and the vehicle are moving. If they both move at different speeds, or in different directions, so that the distance between them is changing

The radar device cannot determine whether the object is moving, if the radar is moving, or if they are both moving. A radar device just determines how fast they are moving relative to each other. It is up to the operator to interpret this data and also account for any errors that could affect it.

Part of every training course deals, or should deal, with the errors that can affect a radar reading. While the technology is impressive, it is not foolproof. If you believe that you were clocked at an inappropriate speed, you might have a defense.

Common factors like weather conditions, curves in the road, or surrounding objects can all affect radar readings. Mechanical situations such as bent antennas or faulty power supply can also produce an inaccurate reading.

A fundamental part of radar technology is how information is received. Due to the fact that relative motion is monitored through radio waves, it is possible for a radar device to pick up other cars or objects instead of a specific one. That’s why it is crucial for the operator to know and implement failsafes against it. Trained defense attorneys understand these pitfalls and how to verify that the device was properly working.