Using Faulty Radar as a Speeding Ticket Defense

One of the most common methods a police officer uses to determine if someone is driving too fast and therefore subject to a speeding ticket is radar. While this technology has made it far easier for law enforcement officials to catch speeders, it has also introduced the concept of faulty radar readings as a means of defending against these types of charges. However, in order to use this defense, it is vital to have solid evidence to prove it in court. Statistics show that as many as 25% of all speeding tickets are the result of faulty radar. However, unless a defendant has evidence to prove it, judges will rarely accept that defense and the speeder will generally be convicted.

Arrest Details

One of the best ways to start compiling an effective defense is to know what the court will use as their offense. To do that, it is important to obtain a copy of the arresting officer’s notes. This is allowed in most states, and it is generally possible to obtain operating instructions and repair manuals for any equipment used. However, few people avail themselves of this option, causing some precincts and courts to ignore such requests. There are three steps to work around this reluctance:

  • Call the police station or local court and learn the procedure for requesting the officer’s notes. In most locales, this means putting the request in writing and sending it to the police station and the prosecuting attorney
  • If there is no response to this letter, go to court and have a lawyer make a “pre-trial motion” requiring that information
  • If the court date arrives and there is still no response, ask that the case be dismissed.

Faulty Radar Defense

It is important to investigate the type of radar device used, it’s maintenance and calibration requirements, and its accuracy record. Receiving the manuals, instructions, and maintenance handbooks for this equipment is the first step. However, other information can be found on the internet showing weaknesses in the system, such as:

  • Shadow Error – in comparing the speed of the officer with that of another vehicle, at times the radar can register a “shadow” effect and add them instead of compare them. That makes the officer believe the suspect is exceeding the speed limit.
  • Cosine Error – the transmission angle of the speed gun can affect the results. Often this causes registry of a lower speed than the actual speed of a suspect, but it is an example of a weakness in the system.
  • RFI Error –radio frequency interference can cause a radar gun to malfunction in the presence of commercial radios or other police radar devices.
  • Mechanical Interference – even the police car’s own heater or air conditioner fan can cause enough mechanical interference to cause a radar gun to register a stationary rock at 70 mph or a palm tree at 28 mph.

Getting Legal Help when Citing Faulty Radar as a Speeding Defense

Faulty radar will not be an effective defense unless there is specific evidence of errors in that type of radar and the defense can prove that those conditions existed at the time of their arrest. In addition, it is important to present that evidence logically, which a nervous defendant often cannot do. Speeding ticket lawyers have appeared before many judges and used these kinds of defense strategies many times. They can compile and present this evidence in such a way that the court will see its credibility and consider it as a viable reason to drop or reduce the charges against a defendant.

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