AN OXFORDSHIRE police officer wants to bring US-style checks for drug-driving to Britain after two weeks’ training with California’s Highway Patrol.

Oxford-born Pc Bob Merrill says his ability to spot drug-drivers has improved after learning about US-style Field Impairment Tests in 14 days of patrols and tests in south Sacramento.

Practices not used by Thames Valley Police include pulse, blood pressure and body temperature tests.

Pc Merrill also learned the horizontal nystagmus test which detects involuntary jerking in drug takers’ eyes as they attempt to focus on a pen in front of them.

The test helps discover whether a driver has taken a depressant, anaesthetic or an inhalant such as sniffing glue, aerosols or lighter fluid.

The 48-year-old, a member of Thames Valley Police’s new road death investigation unit at Bicester, spent £3,000 of his own cash to take the course. He is one of only five serving UK officers qualified to administer the tests.

Pc Merrill, who has been a roads police officer for nine years, and trains TVP officers to perform impairment tests, said: “I think these tests are more precise as they help you narrow down the types of drugs people are on. These are all vital tests and I think they should be brought into law here.”

After two weeks’ intensive training Pc Merrill went out with California’s Highway Patrol and correctly identified 11 drug drivers, or ‘tweakers’ as they are known in the US, out of 12.

He incorrectly identified what one driver had taken as the arrested man had taken a cocktail of drugs.

Tests used by UK forces include measuring pupil dilation, walking in a straight line, standing on one leg and touching the nose with the finger.

The Romberg Test also sees a person asked to tilt their head back slightly, close their eyes and estimate the passage of 30 seconds.

The Department for Transport (DfT) estimates that one in five drivers or riders killed in road accidents may have an impairing drug, legal or illegal, in their system.

In 2008, drugs were reported as a contributory factor in 60 road deaths, approximately three per cent of all fatalities.

They were also factors in 280 serious injuries and 745 slight injuries, but the DfT says this is likely to be an underestimation.

Drug-driving: The Law Drug-driving is illegal under the 1988 Road Traffic Act.

Police have the right to ask drivers to undergo a field impairment assessment, even if they have been pulled over for an unrelated matter.

Drug-driving convictions will lead to a minimum 12-month driving ban, a criminal record and a fine of up to £5,000.

The Government says car insurance will increase “significantly” from a conviction and may restrict access to other countries.

A note will be kept on the driver’s licence for 11 years about the conviction. The maximum sentence for death by dangerous driving that results from drug use is 14 years.

The law does not distinguish between legal and illegal drugs.