Hertfordshire police have welcomed the new drug driving legislation, which came into force on Monday.

The new law will not only make it easier to catch and convict drivers using illegal drugs, but also certain legal medication.

Low limits have been set for eight well known illegal drugs, including cannabis and cocaine. This means that drivers and motorcyclists using even the smallest amounts of these drugs can be prosecuted.

Levels have also been set for eight prescribed drugs, such as pain killers and sleeping or anxiety pills, including morphine and diazepam, which can affect a motorists ability to drive. However, the limit on these drugs are higher to allow motorists to drive legally as directed by their doctor or pharmacist.

Officers from the road policing unit will be using a new roadside testing kit to test for cannabis and cocaine in a drivers system.

The Field Impairment Test, which has been used up to now to assess drivers suspected of taking drugs, will continue to be used where officers suspect that the driver has used other drugs.

Chief Inspector Richard Hann, Head of the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: "We welcome the new legislation. Like alcohol, driving under the influence of drugs can impair the judgement of drivers and slow down their reaction times behind the wheel.

"Driving under the influence of drugs is unacceptable and it puts themselves and others at risk. The introduction of this more simple legislation means it is easier for us to tackle drug drivers of both legal and illegal substances."