Thousands of motorists who received speeding convictions on the M42, may be let-off after signs displayed by the Highways Agency were not compatible.
The signs, which were located on the motorway west of Coventry, showed the speed limit 'taller and narrower that they should have been', said Crown Prosecution Services.
More than 11,000 motorists were convicted between J9 and J7 on the M42 last year.
Despite the Crown Prosecution Services' allegation, the Highways Agency said it believes that the signs were the right size and were clearly visible to motorists.
More top news
Sunny spells on Friday after a frosty start, with only isolated wintry showers, mainly over the hills. Cold with a brisk northerly wind.
Brisk northwesterly winds will bring scattered showers with some bright or sunny spells developing in between. A widespread frost overnight.
Arthur 'Bob' Gumbley was beaten and robbed in his own home before he died in hospital.