Photo: PA
Lord Adonis, the Transport Secretary, has asked legal expert Sir Peter North to advise on the case for changes to drink and drug driving law.
He is expected to recommend that England falls into line with other EU countries by reducing the legal limit from 80mg of alcohol per 100 millilitres of blood to 50mg.
Drinking a standard glass of wine or a pint of beer would push someone of average build over the new limit. Slight women would be able to drink even less.
Sir Peter will also assess the case for introducing a tiered system of punishments, so that drivers with more alcohol in their blood face stiffer penalties.
At present, anyone caught driving over the 80mg limit faces an automatic 12-month ban. It could be that Sir Peter will recommend a 50mg limit but drivers caught, say, between 50mg and 80mg would not automatically be banned.
Sir Peter will advise on whether there is a need for new legislation for drug driving.
It is already illegal to drive while impaired by a drug but a new offence might make it illegal to drive with named drugs in the system at specified levels, in the way that it is already an offence to drive with a specified level of alcohol in the blood.
Sir Peter, who will act wholly independently in publishing his conclusions and advice, will report by the end of March next year.
The announcement came as the Government launched a £1.2 million Christmas anti drink-drive campaign.
This includes a new driver-friendly initiative which will see designated drivers at thousands of pubs across the country receiving free or discounted soft drinks.
Lord Adonis said: ''Road safety has improved significantly in recent years – 1,000 fewer people now die on the roads in a year than in the mid-1990s – and Britain now has one of the safest road systems in the world.
''But we need to cut further the number of tragedies on our roads. Drink-driving killed 430 people last year and research suggests drug driving is a key concern for the public.''
He went on: ''To reduce drink- and drug-driving accidents there may be a case for further strengthening the law. I have appointed Sir Peter to provide me with independent advice on lowering the drink-drive limit and tackling drug-driving through a new offence.''
Sir Peter said: ''Driving under the influence of alcohol or drugs still leads to a large number of deaths and serious injuries. The challenge is to see whether changes in the law and its processes can reduce casualties.
''The legal and practical issues are not easy to resolve but I intend to consult widely on these matters.''
Last month the Scottish Government said it would use its new road safety powers to reduce the limit to 50mg. Legislation is expected early next year.
The current 80mg limit equates to one-and-a-half small glasses of wine or one-and-a-half pints of normal strength beer.
File photo of Transport Secretary Lord Adonis.
The U.K. Government announced today it has commissioned a report on whether the legal alcohol limit for driving, and whether the laws on driving under the influence of drugs, should be tightened.  The report, by Oxford University academic Sir Peter North, should be completed by April for the Secretary of State for Transport, Lord Adonis.  Lord Adonis said, "Drink-driving was involved in 430 road deaths in 2008 and research suggests that drug-driving is also a key concern for the public."

One option that will be considered is whether to lower the limit from 80 milligrams of alcohol per 100 millilitres of blood to 50 milligrams.  This would bring the UK into line with other European countries; a proposal to change the law in Scotland under devolved powers has already been put forward by the Scottish Government. A limit of 50 milligrams would mean that an average person would not be permitted to drive after drinking a standard measure of wine or a pint of beer.

The news was applauded by representatives of motoring organisations. The Automobile Association's President, Edmund King, said he was "pleased that these complex issues will be addressed". The RAC's spokesman said drug-driving is a "growing problem", and lowering the alcohol limit would reduce fatalities. However, the Conservative Party took a different view, with Shadow Transport Secretary, Theresa Villiers, saying they were "yet to be convinced of the case for an across-the-board reduction in the drink-driving limit", and, would certainly oppose any suggestion of penalties being reduced.

Sir Peter North, 73, is a former Principal of Jesus College, Oxford and Vice-Chancellor of Oxford University. A former member of the Law Commission, he chaired the Road Traffic Law Review between 1985 and 1988, leading to the Road Traffic Act of 1991.  His 1997 report on parades and marches in Northern Ireland led to the foundation of the Parades Commission. Commenting on his task he stated, "the challenge is to see whether changes in the law and its processes can reduce casualties", adding that whilst the issues "are not easy to resolve", he intended to consult "widely".