Thousands Were Fined Because of a Fake 50mph Sign. Police Refuse to Cancel a Single One

• A rogue 50mph sign stood on the A20 at Sidcup in January 2024 — on a stretch where the limit had just been cut from 70mph to 40mph, with average speed cameras running.
• Thousands of Drivers received NIPs, and one specialist solicitor estimated as many as 62,000 offences may have been committed in six weeks.
• Police admit the sign should never have been there. What they did next is the part every Driver needs to hear.

In January 2024, a 50mph speed limit sign appeared on the A20 at Sidcup, in south-east London — put up, according to Transport for London, by an “unauthorised third party”.

It stood beside a road whose limit had just been slashed from 70mph to 40mph, with average speed cameras enforcing the new limit around the clock.

Drivers obediently crawling along at 40mph saw the 50 sign, sped up as any reasonable person would — and drove straight into a penalty.

The scale of what followed is hard to take in. One specialist Motoring solicitor advising affected Drivers estimated that as many as 62,000 offences may have been committed on that stretch in just six weeks.

The police admit the sign should never have been there. They are even investigating whoever installed it for a possible attempt to pervert the course of justice.

And they have refused to cancel a single fine.

A Flooded Road, a New Limit — and Chaos

The story starts in October 2023, when Transport for London cut the limit on the eastbound A20 between Sidcup and the Swanley Interchange from 70mph to 40mph, citing persistent flooding on the carriageway.

Regular users of the road said the change was poorly communicated, with many insisting they simply never saw adequate signs telling them a dual carriageway they had driven at 70mph for years was now a 40mph zone.

The tickets piled up fast — and for Drivers who used the road daily, they piled up in multiples. Jonathan Devito, who drives for a living, collected three penalty notices on the stretch and told the BBC he feared losing his licence and with it his income.

Then, in mid-January 2024, the rogue 50mph sign appeared near the Swanley bypass, standing for somewhere between one and eight days by the Metropolitan Police’s own account, before it was spotted and replaced with the correct 40mph signage.

By then, the damage was done — and the appeals began.

The Answer That Stunned 600 Drivers

Around 600 Drivers came forward to contest their penalties on the basis of the fake sign. The Metropolitan Police’s response was that none of them would have their fines waived.

The force said its prosecutions team had taken legal advice, and that the location of the 50mph sign “would not have impacted” enforcement of the 40mph average speed limit. The reasoning: a Driver who had travelled at 40mph through the section and only accelerated to 50mph after passing the rogue sign would still have recorded a legal average speed — so anyone who was ticketed must have been exceeding the limit elsewhere too.

Twelve local MPs were unconvinced, and wrote to the Mayor of London urging him to have the fines cancelled.

The fines stood.

Which left every affected Driver with the same two options: accept the points, or fight the case individually. And one of them did exactly that.

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The Driver Who Fought Back in Court

Jamie Foster, a 28-year-old with a previously clean licence, racked up 12 penalty points in just seven days on the same stretch of the A20 — enough, under the totting-up rules, for a six-month driving ban.

His case went before Bromley Magistrates’ Court in 2024, where his defence argued the signage on the road was “inadequate”. The magistrates clearly saw force in that argument, because instead of the six-month ban hanging over him, Mr Foster was banned for just 28 days.

Nothing about the road changed between his offences and his hearing. The cameras were the same, the limit was the same, and the police position was the same. What changed the outcome was that his circumstances were properly argued in front of a Court, rather than quietly accepted at the kitchen table.

What the A20 Saga Teaches Every Driver

Here is the uncomfortable lesson from the A20: even when the authorities openly admit something went wrong on their side of the fence, fines are not cancelled out of fairness or goodwill. Each Driver was left to fight their own corner — and the Drivers who put a proper argument before a Court did measurably better than those who simply paid up.

If a NIP lands on your doormat, the existence of a defence or of powerful Mitigating Circumstances is worth nothing unless somebody who knows the system puts it forward properly.

That’s exactly what DriveProtect™ Members get: direct access to a specialist Speeding Solicitor who reviews their case and advises them exactly what to respond, for a fraction of the normal cost of legal help.

Got a NIP or points on your licence right now? See how DriveProtect Membership works — a specialist Speeding Solicitor in your corner from £25/month.