Thousands of drivers are being caught out after Britain's biggest police force cut its 'speed tolerance' by 1mph without announcing it, according to reports.
The Times reported that the Metropolitan Police cut the leeway it gives to drivers exceeding the speed limit in 2019 but didn't make any announcement on the tougher rules, leading to more motorists being penalised for driving too fast.
Driving over the speed limit is an offence, but drivers are often given some leeway by police forces, usually calculated by a formula that is 10 per cent of the speed limit plus 3mph, meaning they won't face a fine or punishment providing it's below that.
However, The Times reported that the Met had changed its tolerances in May 2019 from a formula of 10 per cent plus 3mph to 10 per cent plus 2mph, but did not announce it, saying: "Posted speed limits are the maximum speed that road users should travel at any time ... irrespective of the speed threshold that police commence enforcement action."
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The tougher rules led to a 259 per cent hike in the number of motorists being penalised for driving too fast, the report claimed, after comparing figures from the six months before the change to the same period this year.
According to the report, other forces still use 3mph as part of the formula, but speeding enforcement could become stricter across the country with plans to review national guidance.
But experts have warned that it is never sensible to rely on tolerances or having some leeway when it comes to speeding.
AA president Edmund Kind told The Times it isn't worth "chancing your licence or indeed a potential road collision" by relying on "unwritten levels of tolerance".
Solicitor Nick Freeman, who has defended celebrities including David Beckham and Andrew Flintoff in speeding cases, agreed, telling the newspaper: "Many motorists just assume that they have the right, an entitlement to exceed the speed limit by that tolerance. From a legal perspective, they’re wrong."