The latest campaign against drink-driving warns it takes less alcohol than people think to impair their driving. Is the Government right? Joe Willis finds out.

PULLING away from the kerb, the car lurches towards the centre of the road and over the white line, narrowly missing an oncoming lorry.

I overcompensate, turning the steering wheel too far the other way. The vehicle swerves back towards the edge of the road and a waiting lamppost.

Ten minutes earlier I had a drink and its effect on my driving was sobering.

Luckily, my passenger, Inspector Chris Charlton, of North Yorkshire road policing unit, and I were in the safe confines of a driving simulator at the University of Leeds.

More realistic than any computer game, the converted Rover 216 GTI is surrounded by TV screens and can replicate any number of hazards and driving conditions.

I had been invited along to test the message in the Government's latest drink-driving campaign, that even one drink could be too much.

After drinking a double vodka and orange, I had 30 micrograms of alcohol in 100 millilitres of breath. This is within the legal limit of 35 micrograms.

But although I did not actually crash, my driving was far from safe.

I found it difficult to drive in a straight line without slowing to pedestrian speeds.

And traffic lights posed problems as I found it hard to judge distances.

When not covering his eyes with his hands, Insp Charlton observed my performance.

"When you first started you were quite relaxed and you were obviously in control of the car," he said.

"But as the drink kicked in, it became clear your driving was becoming impaired. It was far more erratic and your movements became more exaggerated.

"Had this been a real car, I would have been quite concerned if someone had stepped off the pavement or a car had pulled out in front of us."

Samantha Jameson, a professor of psychology at the university, explained the dangers of drinking and driving. She said: "Just one drink can reduce your reaction time to unexpected events. For example, a car pulls out of a side road and it will take longer to step on the brakes. Alcohol also increases your confidence.

"It makes you feel like a better driver than you actually are.

"The two together mean you could find yourself in a more dangerous situation than you would normally be, without the skills to cope."

Last year, 560 people were killed and 2,600 were seriously injured in drink-related crashes in Britain.

The Department of Transport hopes to get its Christmas message across and reduce the casualties by using television and Radio advertisements, as well as printing warnings on milk cartons and beer mats.

In common with many people, I sometimes enjoy a pint after work or a glass of wine with a meal in a restaurant and then drive home. In future, I will stick to lemonade.