Carrying out speed enforcement checks

Speeding is a concern raised with us at every public meeting, and we are often asked to carry out speed checks in South Cambs villages.  Enforcement work by police officers is one approach to tackling speeding drivers alongside engineering (changing the road layout) and education (changing driver behaviour).  There is often an expectation that police officers should be able to carry speed enforcement on any given stretch of road, but this isn’t the case.  Some roads are just not suitable for roadside checks as Pc Moss describes below.  In such circumstances, agencies might look to one of the other options to address the problem. 

Pc Moss has written a short diary piece describing the practicalities we have to take into account when officers carry out speed checks which I hope you find informative (although there are not too many trade secrets divulged!).  He was accompanied by Pc Nightingale who has recently joined us on completion of her initial training, and both set out to target speeding at locations raised with us by local residents. 

If you have any feedback on the article then “tweet” us, send us an e-mail via the Force website, or come along to your next panel meeting.

Chris Savage



My Name Andy and I have been Policing South Cambridgeshire for a while now;  several years on rural at Histon, some city centre in Cambridge and a stint on traffic for four years for my sins. Now I am in the new Station at Cambourne.

Speeding is a common problem, particularly in rural areas. It is not necessarily speed itself that causes accidents but rather inappropriate speed for the location or conditions; In snowy weather 10 MPH could be too fast, outside a school on at kicking out time, regardless of the weather, 30MPH may be a risk. Whilst common sense applies, a speed limit is a MAXIMUM allowable and not a target to achieve. 

On Thursday this week, I was tasked to do some speed checks in some areas of concern raised by local South Cambridgeshire residents. Ever keen to rise to the challenge, I started early and picked up the LT20-20 Laser speed detection device, (as it`s is not so commonly known, honestly!) and headed out.

First thing to do was check the Calibration certificate on the laser to ensure it was in date and then a check on the scope alignment and accuracy of the laser at a designated range in the yard, followed by a check of the Police vehicle I was using. Lights, tyres, oil and water all ok; kit in the back including cones and signs all in order and I then I headed out. On the way I picked up my colleague, Anna who was tagging along and we made our way over to Barton road in Haslingfield. 

This is a good location: it is a 30 MPH speed area with a long line of clear sight. Guide lines indicate that an Officer must be not less than 2/10th of a mile, (about 300 meters to those less aged than me) inside the speed limit to give drivers sufficient time to adjust to the new road environment. From a safety point of view If I am going to be stepping into the road to stop a car which is exceeding the speed limit, I want to be seen early and give the driver enough time to stop safely without risk to other road users. This is a major consideration: doing speed checks and stopping cars in the wrong location can pose a risk to everyone and defeat the object. National speed limits in rural areas are particularly difficult in this sense. Even if you manage to stop a speeding car safely, ( bear in mind in this case it could be travelling at 70 or 80 plus miles per hour and standing in front of it with one arm raised dressed all in yellow is just asking for trouble) you have no where for the driver to park while you deal with them without adding to the hazards on the road. 

Anyway, back to Haslingfield. Laser checked for alignment again at the road side, fine weather, great visibility, good line of sight, safe place to park cars near the curb and we were off.

Forty five minutes later, one driver reported for excess speed, several warnings issued, numerous cars checked for insurance and MOT, we headed off to the next location. 

This was to be Station road in Harston. On the face of it, another good location; a school inside a 30 MPH limit, cars approaching from a National speed limit area and footpaths to both sides. Even as I was putting on my hat and coat I could see cars whipping past in excess of the limit.

But it was not to be. The only safe place to park the Police vehicle, with sufficient line of sight for oncoming cars was less that 150m inside the 30MPH limit. It just wasn`t enough. (300m is the guideline as you recall). Still, several drivers were spoken to and reminded that there was a school only 50m away and the road wasn`t a race track. 

Even as we did the checks, Anna and I were aware over the radios that several “jobs” had come in and our colleagues were being pressed to manage, so we volunteered for one not too far away and headed to that, leaving Harston behind. 

A little later that shift, I checked the laser again for accuracy and alignment in the yard as is necessary for evidence purposes and put it away for another day. 

The next day was to be that other day.  Once again, Laser, car and kit all checked and I headed off to pick up Anna. Not such a good day today, it was raining. It was June of course and Wimbledon fortnight so not much of a surprise but it was a hindrance. Laser speed checks and rain don`t mix well. For a start it`s wet and the back of my neck has a particular aversion to cold wet rain, but more importantly, it can sometimes, in very heavy rain, effect the ability of the device to “lock on” to a car. It doesn’t mean inaccurate speeds registered but rather the device just saying “Error” all the time. 

Onwards and upwards as they say, so off to Cambridge road in Coton this time. Another good location with safe parking and a good line of sight in a 30 MPH limit. Laser checked and we stood in the rain. The laser was fine and I am pleased to say no one was exceeding the speed limit today; my favourite result. Lots of people saw us, so the message clear and if no one was exceeding the limit it, our work there was doing its job. 

Once again, as the morning progressed, more and more “jobs” came in so we resumed from Coton to back up colleagues. 

There are lots of other locations around South Cambridgeshire with speeding problems for me to look at, so if you see an old Policeman in yellow don`t forget to wave. I`m sure you won`t be going too fast will you?