Drivers Were Wrongly Fined by a Speed Camera Fault for Four Years
National Highways has confirmed that a fault in its variable speed camera network wrongly flagged drivers for speeding on motorways and major A-roads for at least four years. The agency has now identified 2,650 erroneous camera activations dating back to 2021, and an independent investigation is examining cases stretching as far back as 2019.
The fault sat in the gap between a variable speed sign changing and the camera behind it updating to match. For a few seconds, a driver could pass a sign showing a new, higher limit while the camera was still set to the old one. Anyone caught in that window was recorded as speeding for driving at a limit the road had already displayed to them.
How the Fault Came to Light
According to the Department for Transport, National Highways first flagged the problem on 10 September 2025, after a driver challenged a speeding offence issued on the M5. Ministers were told the anomaly was a national issue on 13 October 2025. National Highways then confirmed the scale of the problem publicly on 15 December 2025, in a guidance notice published on gov.uk.
The fault affected 154 cameras across roughly 10 percent of the strategic road network, the motorways and major A-roads that National Highways operates and maintains in England. Every variable speed camera on the smart motorway network falls inside that 10 percent, alongside two cameras on the A14.
National Highways points out that the 2,650 erroneous activations sit against more than 6 million total camera activations on the affected roads from 2021 to now, putting the error rate below 0.1 percent. Not every one of those 2,650 activations led to a fine. Some were caught before enforcement, others fell to a driver’s challenge, as happened on the M5. But the agency has not said how many drivers were actually prosecuted, fined, or had points added to their licence as a direct result of the fault.
Who Is Responsible for Fixing It
National Highways operates the camera and signage infrastructure, but the agency is not a law enforcement body. Every activation is passed to the police force covering that stretch of road, and officers decide whether to prosecute. That split is worth knowing before you try to work out who to contact: National Highways owns the technical fault, but the police hold the case files and issued the fines.
National Highways chief executive Nick Harris said the organisation had “developed a fix for this technical anomaly to maintain the highest levels of safety on these roads and make sure no one is wrongly prosecuted.” Transport minister Simon Lightwood confirmed the Department for Transport has ordered an independent investigation into how the fault happened and how long it went undetected, with National Highways separately reviewing camera data back to 2019, the year it began upgrading its variable speed camera network.
A data check has now been built into the camera system to stop the anomaly triggering further incorrect enforcement, and National Highways says it is working with police forces on how to apply it.
What Happens If You Were Affected
Gov.uk guidance is direct on this point: drivers do not need to take any action at this stage. Anyone affected will be contacted directly by the police force that issued their fine. Where the anomaly caused a wrongful conviction, the fine will be refunded and any penalty points removed from the driver’s licence, though gov.uk gives no fixed timescale for when that contact will happen.
That passive approach will frustrate drivers who suspect they were caught by the fault years ago and have already paid a fine or accepted points onto their licence without ever knowing why. If you were fined for speeding on a smart motorway or a major A-road with variable speed limits between 2019 and today, and you were confident you were driving within the posted limit at the time, it is worth keeping your paperwork and any dashcam footage rather than assuming the case is closed. The independent investigation is ongoing, and its scope could widen.
For anyone currently contesting a speeding notice from a variable speed camera, raising the anomaly directly with the prosecuting police force is a reasonable step, especially if the alleged offence falls on one of the smart motorway sections where every variable speed camera was in scope of the fault.
A Pattern Worth Watching
This is not the first time enforcement technology on England’s roads has come under scrutiny for accuracy. Smart motorways themselves have faced years of criticism over stopped-vehicle detection reliability, and the National Highways admission follows a familiar shape: a technical problem identified through an individual’s legal challenge, rather than through the operator’s own monitoring, with the true scale only becoming public once a driver pushed back.
The independent investigation now underway will need to establish not just how the delay between sign and camera occurred, but why it took until a driver disputed a single M5 fine in September 2025 for the four-year pattern to surface. Until that review reports, drivers on the affected 10 percent of the network are relying on a fix that has already been rolled out, and a promise that anyone still owed a refund or a points removal will eventually be contacted.
Full details of the anomaly, including updates as the independent investigation progresses, are published on gov.uk’s dedicated guidance page, which the Department for Transport has committed to keeping current as more cases are identified.
Checking Your Own Record
Drivers can check the points and endorsements currently held on their licence for free through the government’s “view your driving licence” service on gov.uk, using their driving licence number and National Insurance number. That check will not tell you whether a specific speeding endorsement came from a faulty camera activation, as National Highways has not published a route by route or date by date list of the 2,650 affected cases, but it does give you an accurate current record to compare against your own memory of where and when you were caught.
If your licence shows points from a speeding offence on a smart motorway section, and you remember disputing the reading at the time or being surprised by it, that is a stronger reason to raise the case with the police force that issued the original notice than simply waiting for a letter that might never arrive. Points from a speeding offence typically stay on a licence for four years from the date of the offence, so anyone caught by the fault as far back as 2021 could already be close to the point where the endorsement would have expired regardless, which adds pressure to resolve genuine cases before that record disappears from view.
Why Variable Speed Limits Exist in the First Place
Variable speed limits were introduced on England’s busiest motorways specifically to smooth traffic flow and reduce the stop-start braking that causes many motorway collisions, lowering the limit automatically when sensors detect congestion building ahead and raising it again once traffic clears. The system depends entirely on drivers trusting that the limit shown on the gantry above them is the limit actually being enforced at that moment. A camera that lags behind the sign undermines exactly the trust the technology needs to work, as a driver doing everything right, watching the gantry and adjusting speed accordingly, was still at risk of being logged against a limit that had already changed.
National Highways has not said whether the fault ever ran in the opposite direction, allowing a driver travelling faster than a newly lowered limit to escape detection in the same lag window. The published guidance focuses only on wrongful enforcement, which is the scenario that produces refunds and points removals, but it leaves an open question about whether the anomaly also affected the accuracy of the network’s underlying safety case in those seconds of mismatch between sign and camera.
Sources:
- https://www.gov.uk/guidance/national-highways-variable-speed-camera-anomaly
- https://nationalhighways.co.uk/press/fix-being-rolled-out-after-variable-speed-camera-anomaly/
- https://www.highwaysmagazine.co.uk/news/strategic-road-network/600-incorrect-variable-speed-camera-activations-2021
- https://www.fleetnews.co.uk/news/independent-review-of-national-highways-speed-camera-fault-launched