'Mind the boy doesn’t vomit over you,” said Sergeant Rob Leet as he put the drunken, bruised teenager into the back of his squad car. I was on patrol on Friday night with Brighton’s Operation Athlete which targets the seaside town’s underage drinkers. Fifteen-year-old Harry had been beaten up.

As part of their “boozebuster” initiative, the police and council in Brighton and Hove are sending dedicated police patrols to clamp down on underage drinkers on the city’s streets, beaches and parks.

Every weekend at least six Operation Athlete officers break up kids’ parties, take the drunkest home and demand that parents exert discipline - or else.

They liaise with schools and social services about those whose parents do not care and “confiscate lakes of booze”: in the past six months 1,000 cans of beer, 70 bottles of wine and 13 bottles of spirits. Other officers spy on shops selling booze to those underage. Several have already lost their licences.

Leet confides sadly that trendy middle-class parents dislike Operation Athlete, believing it challenges “little Oscar’s human right to get tight in public”. Yet the same people bitterly complain about vandalism.

Brighton’s affluent Preston Park area has suffered 50% less vandalism and burglaries since a police crackdown last year on underage drinkers.

I first saw Operation Athlete in action in Palmeira Square, Hove. Its landscaped gardens were once regularly colonised by noisy, drunken youngsters. Then one night a paddy wagon arrived and two coppers, apparently at random, chased two boys.

Within minutes the crowd had panicked and run and the square was again calm. Leet explained: “That’s ‘theatre policing’. If you’ve got a big group, you can’t deal with them all so you target the known troublemakers. If we arrest someone, there’s so much paperwork that that’s us out of the equation for the rest of the night.”

They rely instead on charm, confiscation, good behaviour contracts and antisocial behaviour orders. “Asbos isolate ringleaders and break up kids’ social groups, and the rest of the group usually grow up,” he said.

Throughout the evening I was surprised by how respectful the kids were when challenged. Sergeant Chris Lane, the patrol driver, said: “The kids who drink aren’t particularly bad; they do their homework, go to school. It’s just the culture, what they think is normal on a Friday night.

“I’ve felt kids shaking as we put them in the car; you know that’s a result.”

Next we patrol Preston Park and Fiveways, leafy areas of Edwardian villas where last year up to 30 youths gathered nightly, drinking, screaming and breaking things, until police obtained dispersal orders.

It makes the officers angry that many middle-class parents are unsupportive: “They even buy the booze and tell us kids have to learn to drink. Maybe so, but not by chucking them out onto the street with a bunch of strangers.”

One night they escorted home a 15-year-old girl they had found lying “paralytic” in the fields. Her father, a professional man, was so enraged by the officers bringing home his child that he reported them.

Some parents feel that allowing children to have drink parties at home is safest. But the officers were aghast when they spotted children fleeing a house party where no adults were present. They were holding up a boy who had been battered.

We delivered the lad to his alarmed single mother in a terraced house. Leet helped him to the door but did not deliver his lecture; it was gone midnight and “the boy’s more a victim than an offender”. Then it was back to the station for a drink: a nice cup of tea.

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