Laser Jammers and the law

Laser jammers too risky to useAt present there is no law expressly making the use of laser jammers unlawful, but a number of prosecutions arising out of their use makes it risky to use one.

The consequences can be serious.

There are many devices freely and relatively cheaply available for purchase over the internet that are said to perform a variety of functions from parking sensors to opening garage doors. Some are very sophisticated and the function can be switched by the driver.

Using one to interfere with a speed detection device being operated by a police officer could well result in an arrest and charge for perverting the course of justice.

Perverting the course of justice is a serious offence and on conviction carries life imprisonment. Long term imprisonment tends to be reserved for those who interfere with trials or investigations for example by threatening witnesses.

Nonetheless drivers using such devices to stop or interfere with police speed detection do face a Crown Court appearance and a serious risk of prison and disqualification.

I represented a client who was travelling at a speed modestly in excess of the speed limit. He approached a Traffic Officer deploying a laser device to check his speed, and on each occasion he attempted to do so the device showed “error”.

The Officer was sure something was stopping the device from registering the speed, although it did perform its normal function of recording the vehicle. The video enabled the speed of the vehicle to be checked, by working out how long it took to pass fixed points.  It was easy to see the vehicle was speeding.

In this instance the police obtained a search warrant and attended my client’s home to search his vehicle. That revealed a device fitted behind the front number plate and a police expert was able to deconstruct it and demonstrate its ability to diffuse the laser beam from the speed gun.

My client was charged with perverting the course of justice and his case moved swiftly from the Magistrates to the Crown Court.

Why perverting the course of justice?

The simple answer is that there is no statutory offence committed (because there is no legislation outlawing the use of these devices) and so there is no alternative, with one minor exception. If the operator of the speed gun is a police officer an alternative might be a charge of obstructing a police officer in the course of his duty. That can be dealt with in the Magistrates Court and can be quickly over.

However there is a problem if the person operating the speed gun is not a police constable as properly defined. Many are not and are Police Support Employees with speed equipment training.

The Crown Prosecution Service or even the court may be very reluctant indeed to see a drop from perverting the course of justice to obstruction if the person obstructed was not a police constable. 

What is perverting the course of justice?

The offence is committed where a person:

  • does an act (a positive act or series of acts is required; mere inaction is insufficient)
  • which has a tendency to pervert and
  • which is intended to pervert
  • the course of public justice.

The course of justice includes the police investigation of a possible crime and it is not necessary for legal proceedings to have begun.

In this way it fits the use of a laser jammer.

In my case we had a very helpful Court who was prepared to view it leniently. The CPS was determined to go to trial over knowledge of what the device would do, but the Judge gave an “indication” of what he would do after a guilty plea, and my client left with a modest fine and a conditional discharge. It could have been far worse but he had good legal advice and excellent counsel.



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Comment by gmt - 27th January 2017
John, [I think] you're allowed 10% +2 over the speed limit. So you can do 79mph on the motorway without any issues, however do 1mph over and you risk a speeding office, so keep it 77-78. Source? Well don't have anything available in writing but a police officer in a police documentry said so. Case in point for a speeding conviction in a 30mph road you need to do 36mph or over. I was on a speed awareness course with 30 people and majority did 36mph. In addition to this on another police traffic tv show there were village volunteers who were reporting speeders across their village,. Police advise them they needed to include make, model, colour as well as the reg of the vehicle. In addition to this the police advised the village volunteers to only report on drivers who do 36mph or over [in a 30 road]
Comment by abdul - 22nd March 2016
Great advice David. I have been cosidering fitting one of these devices for a while now, not because I am habitual speeder but will admit to treating the ludicrous 70 mph limit on motorways and certain dual carriageways as for guidance only rather than a limit to be strictly observed. That said, I very rarely exceed 90 mph and NEVER speed in built up areas where pedestrians are prevalent, so some may ask why would I want to fit a laser jammer? The reason being in my experience is that apart from the Mobile Camera vans that have prescribed sites, (the location of which is available in the public domain and in my case, alerted to me by my GPS based camera location device) the police often lie in wait, partially obscured on relatively "quiet" sections of especially dual carriageways where travelling at 85 - 90 mph is perfectly safe, zapping motorists with a hand held lazer gun purely to up their ticketing statistics and it is this underhand and sneaky behaviour which gets my goat. They also seem to target "up market" cars and ignore "Joe Soap" doing 90 in his 2001 Ford Mondeo, a sure sign of 'vehicle envy" by Mr Plod who cant afford a BMW! I dont and never will, advocate dangerous speeding but as far as I'm concerned, dodging the sneaky hand held laser trap used inappropriately is perfectly acceptable if driving safely but as usual, the police cant stand it when you get one over on them so they spit their dummy out and you get nicked for the totally ludicrous offence of perverting the course of justice - much the same in essence as knowingly covering up for a serial killer! Anyway, following your advice I will just have to be more vigilant and until they come up with a device that sends a signal back to the hand held gun operator that completely wipes his memory 'Men in Black" style, a radar jammer is off the menu!!!
Comment by John Worpole - 10th September 2015
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