Sussex motorists are among the most likely to get caught for drink-driving, according to a Government report.

Drivers are more likely to be subjected to a breath test on the county's roads than in most other areas of Britain, the Home Office study found.

Road safety groups said drivers were less likely to risk drink-driving where they knew the police were vigilant.

The Home Office statistics appeared to support this claim with the disclosure that breath tests by Sussex police were almost half as likely to be positive as the national average.

The newly-published figures show that there were 17,200 breath tests in Sussex in 2003 - a rate of 1,143 per 100,000 of the population.

Nationally, there were 1,018 tests per 100,000 people.

Of those who were tested in Sussex, 2,000 drivers - or 12 per cent - were positive or refused to co-operate.

Nationally, 20 per cent tested positive or refused to co-operate.

The Parliamentary Advisory Council for Transport Safety said that drivers were taking advantage of a perceived lack of police vigilance on motoring offences in some areas of the country.

The Association of Chief Police Officers advises that all motorists involved in a collision must be breath-tested.

But random testing is not permitted in Britain, unlike most European countries.

Road safety charity Brake urged the Government to ensure that all forces were following the ACPO guidelines.

A Home Office spokesman said: "Operational decisions are a matter for individual police constables. The Association of Chief Police Officers publishes nationwide guidance for police forces on how to deal with drink drivers."

The Serious Organised Crime and Police Act, which reached the Statute Book earlier this year, aims to make it simpler for officers to enforce the law.

It allows roadside breath-test results to be used in court, removing the need for drivers to be taken back to the station.

The Road Safety Bill, announced in last week's Queen's Speech, will give courts the power to make drink-drive offenders fit devices which tests their breath before the engine will start.