Under the proposals, cars more than four years old would be tested only every other year / getty images
Critics say proposals to reduce car checks could lead to more than 6,000 deaths and injuries a year

The Government has indicated it is keen to relax rules that force motorists to pay for an annual MOT test, despite warnings that the move will cause at least 50 more deaths on UK roads every year.

A government-commissioned study found that the proposal to reduce the frequency of the vehicle checks was "likely to have adverse road safety consequences", particularly for older vehicles.

The Transport Research Laboratory estimated that vehicle defects were a "contributory factor" in around 3 per cent of road accidents. Motoring groups last night claimed that allowing vehicles to be tested every two years could double the rate of accidents and casualties – adding around 55 to the death toll each year.

However, sources at the Department for Transport said the report's findings did not deter ministers. "This is part of an ongoing reconsideration of the MOT regime. It is important to review the system after almost half a century in which vehicle technology has advanced massively. The research does not prove the case one way or the other," one source said.

At present, new vehicles must be tested after three years and then every year thereafter – the so-called 3-1-1 system. The Secretary of State for Transport, Philip Hammond, sparked fury earlier this year when he launched a review that could delay a new car's first MOT test until it is four years old. Another option is to require MOTs, which currently cost £54.85 for private cars, only every other year until the vehicle is a decade old – making the testing timetable 4-2-2-2 – before then reverting to annual checks.

The changes were proposed in an attempt to reduce the financial burden on motorists who have been squeezed by soaring petrol prices. They were condemned by garages, fearing that their MOT income, supplemented by the repairs and extra work required to get vehicles through the test, could be halved.

But motoring groups have focused on the safety implications of allowing vehicles to be driven for longer with potentially lethal defects, such as bald tyres and worn brakes.

Andrew Howard, head of road safety at the Automobile Association, said: "The Government might think the impact of vehicle defects is small, but 3 per cent of 200,000 road casualties is still 6,000 people being killed or injured unnecessarily. A car can pass an MOT one day and develop a defect that would make it fail the next, but that would not be picked up for two years under this system. That's a big risk," he said.

Jonathan Visscher, of the Society of Motor Manufacturers and Traders, said: "Industry's priority is to ensure vehicle safety is maintained to the highest possible standard. The Government's proposals cannot be justified, especially when viewed in the light of the latest EU plans to reduce road deaths. Regular MOT checks are also important to reduce the cost of running and maintaining a vehicle. They enable motorists to identify potential problems in their early stages."

More than 23 million vehicles in the UK are subjected to an MOT test annually, and the current failure rate is at least 35 per cent, with 8.5 million cars found to have defects. Gordon Brown first suggested relaxing the system three years ago but was forced to abandon the plan after a Department for Transport investigation warned the changes would lead to a "significant" increase in the number of deaths and serious injuries.

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