It has been more than 30 years since Britain's first speed camera was switched on over Twickenham Bridge in Surrey. Since the creation of the Gatso camera in 1992, these devices have earned millions in revenue; but do speed cameras work? Are they a reliable technology to reduce driver speed and capture reckless road users? Or are they simply a way to bring in money through the issuing of fines?

Reports vary as to how many speed cameras there are in the UK, but whatever the number, the government believes they are a vital part of its nationwide effort to reduce road traffic accidents. Research has supported this, with a 2017 study estimating that, between 1992 and 2016, speed cameras in the UK reduced fatalities by up to 68% (within 500 metres of the camera). It also estimated that adding another 1,000 cameras to accident hotspots could save up to 190 lives and prevent up to 330 serious injuries each year.

However, the use of speed cameras has changed significantly since then, and there is a lack of data about the impact of newer technologies like average speed cameras, mobile speed cameras and others. This lack of data and variable approach makes it much more difficult to establish whether or not speed cameras are working as intended.

Further, there are many people who beg to differ with the government, including the very man who helped create the speed camera. Roger Reynolds stated in 2012 that the use of speed cameras had been "a fiasco" and said in 2015 that enforcement agencies are now too strict on minor offenders. With the number of caught motorists reaching 1.74 million in 2022, Reynolds may not be far wrong - so are speed cameras still a useful tool or are they becoming an overused nuisance?

How do Speed Cameras Work?

Firstly, we'll begin with how today's speed cameras work when you enter the speed trap. Regular motorists may be familiar with the SPECS average speed camera, which utilises state-of-the-art video with automatic number plate-reading digital technology.

As vehicles pass between the entry and exit camera points, their number plates are digitally recorded, whether they are speeding or not. The images are then paired up and, because each image carries a date and time stamp, the computer can then work out your average speed between the cameras.

It's important to remember that the enforcement authority must send the registered keeper of the vehicle a Notice of Intended Prosecution within 14 days of the date the photo was taken. Otherwise, under most circumstances, they will no longer be able to prosecute the person who was driving at the time of the incident.

How Much Margin for Error is There?

At present, some police forces allow 10% of the limit plus two miles per hour. The National Police Chiefs' Council recommends that this leeway be granted, but according to the law, even one mph over the limit can result in a speeding ticket or other penalty.

As such, whether or not you will be allowed this buffer varies by location and is subject to change at any stage, with or without warning from the relevant police forces. This leeway has always been discretionary, which means that it does not need to be applied to all cases consistently. The relevant police forces have taken into account a variety of factors, and in particular, the fact that speedometers are not always calibrated properly and may not be a true reflection of the speed at which the vehicle is actually moving.

Are Speed Cameras Always Correct?

The original Gatso speed camera detectors don't always work successfully. They have been known to flash on their own without being properly triggered by a speeding vehicle as well as being set off due to vehicles travelling in the opposite direction.

The photos are only used to perform a secondary check of the alleged speed as the driver's speed is determined in relation to markings on the road. However, digital SPECS average speed cameras are proven to be far more reliable as there is no film, and your speed is calculated by time rather than markings on the road.

The latest technology has made this process even more precise, and while it is still possible for cameras to make mistakes, it happens much less often. Average speed cameras work using infra-red light to capture licence plate information, which means that they work in the dark and in bad weather conditions without needing to use a flash. As such, their results are typically very reliable.

What Are the Differences Between Average Speed Cameras and Fixed Speed Cameras?

There are several types of speed cameras in the UK, but the two most common are the average speed camera and the fixed speed camera.

Fixed speed cameras (including the Gatso speed cameras we have discussed above) are placed along roadsides where there is a high risk of accidents, according to local data. They work by taking two photographs in quick succession of each vehicle that passes - then, they compare the position of the vehicle and the time between the images to calculate the speed at which the car is moving.

Average speed cameras (like the SPECS camera), on the other hand, are located at regular intervals along motorways and other roads. A group of these cameras is linked together to capture a vehicle's speed over a longer distance, and calculate an average speed based on this data so as to detect speeding vehicles.

While fixed speed cameras are very visible and heavily signposted to act as a deterrent, average speed cameras may not be as clearly indicated. However, in some cases, they may be placed at either end of a road where a lower speed limit applies - for example, a road that passes through a village - to catch drivers who exceed the speed limit at any point on this journey.

Fixed speed cameras flash when they capture an image but average speed cameras do not, as the technology they use to record your vehicle's speed and licence plate details is different. As such, there is no way to tell that you have been caught by an average speed camera. Therefore, it is always safest to drive at or below the speed limit at all times. In this way, you can avoid penalty points on your licence and other punishments that you may incur by speeding, and ensure that you drive as safely as possible.

A third common type is mobile speed cameras, which work in a very different way. These devices are operated by police officers from their vehicles, which means that they can be positioned anywhere that it is safe to park a car - and in fact, in some cases, they can be used in moving vehicles. Mobile speed cameras work using radar technology, or lasers in some cases, and have a range of up to a mile. Provided the operator can see your vehicle with their radar or laser gun, they can obtain an accurate measurement of the speed at which you are driving.

Alternatives to cameras

Not all areas in the UK enforce the use of speed cameras as harshly as others and, in fact, it's a right that local councils decide how best to tackle specific problems in their areas. One alternative approach proposed by police is to offer offenders a speed awareness course instead of three penalty points on their licence.

Many people still remain not entirely convinced of the benefits of speed cameras. A study published by the RAC in 2018 showed that 50% of British people do not believe speed cameras work as a deterrent, and 83% feel that offenders simply slow down as they pass the camera, before speeding back up.

62% of the study's respondents said they feel that some cameras are used to raise money, rather than to improve traffic flow. On the other hand, two-thirds of respondents reported that they feel that speed cameras are ultimately a force for good in society, and 70% support automation in road traffic enforcement if it leads to a reduction in accidents and casualties.

What Should I Do if I Am Caught Speeding?

The penalties for speeding are not usually severe, but you can receive a fine and penalty points on your licence. If you already have points on your licence - and especially if you passed your driving test within the last two years - you could face more serious consequences, including a driving ban or even the removal of your licence requiring retest. In the latter case, drivers have to pass both their theory and practical tests again before they can legally drive, so it is vital to avoid this outcome.

As such, it is useful to understand what happens when you are caught speeding, what to expect if you are prosecuted, what you need to do in response and the steps you can take to defend yourself. In this way, you may be able to avoid penalty points, preserve your driving licence, and avoid the most serious consequences.

In most cases, the first indication that you have been caught speeding is the receipt of a Notice of Intended Prosecution (NIP). In order for an enforcement authority to prosecute you for speeding, they must send a NIP to the registered keeper of the vehicle involved in the incident within 14 days of the alleged offence. If you do not receive a NIP, this will usually mean that the police cannot proceed with the prosecution. On the other hand, receiving a NIP does not mean that you are certain to be prosecuted - it only allows for the possibility that the police may decide to prosecute.

The NIP informs the vehicle's registered owner that they may be prosecuted for a speeding offence. If they were not driving the vehicle at the time, this also gives them the opportunity to identify the driver. It is assumed that as a vehicle's owner, you must know who is driving your vehicle at all times - if you are unable to provide details of who was driving, you may receive a separate charge of failing to provide information, which can result in a penalty of six points on your driving licence and a fine up to £1,000. When you receive a NIP, you are legally required to provide the requested information, such as the driver's details, within 28 days.

If you are caught by a police officer or other traffic officer using a handheld or mobile speed camera, they may issue you with a verbal warning, NIP in the post or a fixed penalty notice on the spot.

After responding to the NIP, there are several potential outcomes. If the police decide to prosecute, you may receive a fixed penalty notice, which typically includes a fine and penalty points on your driving licence. If this is not your first offence, the punishment can be more serious.

Alternatively, you may be given the option to attend a speed awareness course. This option is usually available for first-time offenders or those caught marginally over the speed limit. You may need to pay to attend the course, but this avoids incurring any penalty points.

If the speeding offence is severe or the driver has accumulated a significant number of penalty points, they may receive a court summons. In this case, the driver will need to attend a court hearing to address the speeding offence and may receive a much more serious penalty if they are found guilty.

How Can I Defend Myself Against Prosecution?

If you receive a NIP and are facing prosecution for a speeding offence, it may be worthwhile to seek legal advice. Consult with a solicitor or legal expert specialising in motoring offences, as there are circumstances in which you may be able to defend yourself and avoid prosecution.

Seeking legal guidance is vital if you have received a court summons, as a solicitor can provide guidance on your options and help you prepare for any potential court hearings. In such cases, you should also gather any evidence that may support your case. This could include photographs, dashcam footage, or witness statements. This evidence may be useful in contesting the alleged offence or mitigating the penalties. If you are unsure about how to do this, your solicitor can help.

The best way to avoid prosecution is to abide by the law at all times, and this includes by driving at or below the speed limit. Make sure you stay aware of the relevant speed limit wherever you drive, and remember that GPS devices may give you incorrect information. If in doubt, follow the speed limit as indicated by signs on the road.

Experts in Motoring Offences

If you have been accused of a motoring offence, including being caught by a speed camera, and require legal advice, take a look at our driving offence services page for more information.

The solicitors at JMW specialise in speeding camera offences where there are grounds for defence against conviction. Call 0345 872 6666, or fill in our contact form to speak to a member of the team about your circumstances.