Thousands of motorists could have their motorway speeding convictions overturned because the font used on some variable speed limit signs may not have complied with traffic regulations.
The numbers displayed on some variable speed limit signs on the M42 were taller and narrower than the regulations, according to the Crown Prosecution Service (CPS).
However, despite the CPS's claims, the Highways Agency has said it believes that the signs, on two stretches of the M42, between junctions 3a to 7 and junctions 7 to 9, were the right size and were clearly visible to motorists.
Warwickshire Police said they were advised by the CPS last November that there were issues with fonts on some of the Advanced Motorway Indicators (AMI) on the M42. As a result, the force took the decision to stop using the signs and dropped pending prosecutions while they referred the matter to the Department for Transport (DfT).
However, thousands of motorists had already received fines and convictions since the signs had gone into operation. At least 11,000 fixed penalties were issued to motorists breaking the variable speed limit between junctions 7 and 9 of the M42 last year, according to the BBC.
Warwickshire Police said the DfT examined the issue and authorised the use of the signs at the end of November last year. The force recommenced enforcement of the cameras on January 1.However, lawyers and traffic consultants are calling for penalties which were handed out while they were in place to be quashed, arguing that they are not legally enforceable.
Richard Bentley, a traffic management consultant and former police officer, told the BBC he thinks it is only fair that previous speeding fines, points and driving bans be reconsidered. He said: "There should be a situation where cases are opened in the magistrates' court to have the cases reheard and the convictions quashed. If there are no traffic signs the Act of Parliament prohibits the conviction and these are definitely not traffic signs."
In a statement, Warwickshire Police said: "An issue arose over whether the variable speed limit signs which gave indication of the variable speed limits complied with the Traffic Signs Regulation and General Directions 2002. The issue related to the shape of the numerals in the signs. Warwickshire Police were made aware of this issue on November 8, 2012.
"As a consequence Warwickshire Police decided to suspend enforcement of these cameras until the issue was resolved. The issue has now been resolved by the DfT signing an authority for the use of these signs on November 27, 2012. Warwickshire Police recommenced enforcement of the cameras on 1st January 2013."
Warwickshire Police's camera enforcement unit manager Gary Hollis told the BBC: "Motorists who have already had their cases dealt with by the courts, conditional offers of fixed penalty or speed awareness courses are advised to take independent advice regarding how this affects their individual cases."