The Government promised that the new offence of drug-driving will not unduly penalise those on properly-prescribed medication.
The pledge from Transport Minister Stephen Hammond came as he published a 200-page Whitehall-commissioned report on drug-driving from King’s College in London.
The report – by a panel of medical and scientific experts – recommends thresholds at a level above which driving is considered dangerous.
The panel has suggested a dual limit when some drugs are found in combination with alcohol.
In relation to morphine, for example, the panel has recommended a drug-drive limit significantly above the concentration of morphine in the blood that a cancer patient might have been prescribed in the long-term.
The panel also said the Government should adopt a similar system to that in Norway where blood samples are routinely collected at all road traffic accidents and analysed against a universal list of substances.
It added that these results should be held in a national database and would provide “much-needed evidence of the consequence of drug-driving”.
The new offence of driving or being in charge of a motor vehicle with a specified controlled drug in the body is included in the Crime and Courts Bill, currently before Parliament.
Mr Hammond said yesterday: “The Government will carefully consider the panel’s recommendations.
“In doing so, we are clear that the design of the new offence must send the strongest possible message that you cannot take any amount of illegal drugs and drive.
“At the same time, the Government must consider the position of those who legitimately and safely use medicines which may contain controlled drugs.”
He went on: “We recognise that for the purposes of drug testing, distinguishing between those drugs which do have medical uses and those which do not is complex.
“We must ensure that the new offence would not unduly penalise drivers who have taken properly prescribed or supplied drugs in line with medical advice.”
He said that later in the year the Government would make specific proposals regarding the drugs to be specified in regulations for the new offence and that these proposals would be subject to a public consultation.
The panel was led by Dr Kim Wolff of King’s College’s pharmaceutical science department.
She said yesterday there were indications that drug-driving could be a factor in 200 deaths a year on the roads.