Martin Catlow did not see anything unusual in the group of yobs causing havoc as he drove home from work. They were shouting, throwing wheelie bins into the traffic, the usual sort of hooligan stuff.

“No one seemed to be doing anything about it so I called the police,” said Catlow. “I was going to leave it at that, but one of them picked up a ‘for sale’ sign and started brandishing it at cars passing by. I don’t know what came over me but I jumped out of my car to confront the youth.”

Catlow has no idea what happened next, because he was kicked to the ground and knocked unconscious by half a dozen youths. He suffered a massive head injury and was told that he could have died.

The attack in daylight in a small village outside Sidcup, Kent, was not completely unexpected. “There had been lots of trouble in the area for weeks. Gangs were going around smashing up shops and causing mayhem. My wife and I saw what was going on but felt powerless to do anything to stop it,” said the 54-year-old businessman.

The danger of challenging antisocial yobs was starkly highlighted last week when Evren Anil, a 23-year-old graduate, died after he confronted a knife-carrying teenager who had thrown a half-eaten chocolate bar into the open window of his sister’s car in south London.

Anil’s death on Monday came three days after that of Garry Newlove, a 47-year-old father of three who died after challenging youths he suspected were vandalising his car outside his home in Warrington.

Were the two men right to have a go or should they have joined the “walk-on-by” society? Has Britain become a country where we prefer to look away rather than take a principled stand and risk injury or even death?

Government and police advice on what to do when confronted with antisocial thuggery has varied from the bizarre to the gung-ho. Earlier this year Tony McNulty, the minister for policing, said witnesses to violent crime should “distract” attackers by honking their car horns or “jumping up and down”. However, law and order experts described him as “irresponsible”.

Standard police advice to people who witness violent behaviour is to call 999 and not get involved. And that, it seems, is the reaction of most Britons.

A report from the Institute for Public Policy Research found that British adults are less likely to intervene than other Europeans. According to the report, 30% of adults in Britain said they would definitely not get involved if they saw a group of 14-year-old boys vandalising a bus shelter. That compares with just 7% of “walk-on-bys” in Germany, 13% in Italy, 17% in Spain and 19% in France and Holland.

Even Scotland Yard seemed flummoxed when asked how citizens should behave. “We advise people to judge the circumstances and not to put themselves in danger,” was all a spokesman would say.

Things were simpler 30 years ago, when Britain still imagined itself in the Dixon of Dock Green era and many would not have thought twice about “having a go”. Cliff Lyons, the Metropolitan police detective investigating Anil’s murder, said that spirit still prevailed: “People are entitled to challenge these yobs’ behaviour.”

David Green, who as director of Civitas, an independent think tank, has studied flaws in the official crime figures, takes a sharply different view: “When I was younger, if someone was smoking in a no-smoking carriage you would say something. I haven’t done that lately because you’d have to be prepared for a fight.”

Bernard Hogan-Howe, the chief constable of Merseyside, is not convinced that it is more dangerous to challenge people today than it was a generation ago: “There’s always been some danger in intervening. If you can’t get hold of the police or you think it’s not serious enough, then try to get other people to join you in challenging bad behaviour. At least then you’ve got the safety of numbers.”

Ray Mallon, the former policeman dubbed “Robocop” who is now mayor of Middlesbrough, said antisocial behaviour should be society’s priority. “We’ve got to fight for every inch of every street. In the past we’ve failed to intervene and look where we have ended up. If we don’t get a grip now, I’ve no idea where we will end up in 25 years,” he said.

He believes thuggery is on the rise because unruly youngsters no longer fear or respect the police: “The police need to get out onto the streets. I want to see the fear transferred from the victim, the ordinary citizen, to the yob.”

Richard Garside, director of the Centre for Crime and Justice Studies (CCJS), an independent think tank at King’s College London, said: “Labour has wobbled over the years on its advice. As home secretary in the late 1990s, Jack Straw called on the public to have a go. David Blunkett asked the public to ‘take a stand’ against antisocial behaviour. Now the advice appears to be to call the police.

“Yet the police can hardly be expected to swoop down on every group of teenagers hanging out in hoodies.”

Even the question of just how dangerous it really is to confront yobs is difficult to assess because of grave doubts about the accuracy of government crime figures. Ministers lament that the public’s fear of crime is radically out of line with its actual level. Successive home secretaries have been fond of quoting the British Crime Survey which shows that overall crime has fallen by a third in the past decade. The most recent survey, published last month, states that the risk of becoming a victim is 24%, compared with 40% in 1995.

Independent experts say the figures are misleading because they fail to highlight a rise in violent crime, especially cases involving knives and young people.

A study sponsored by The Sunday Times and published by the CCJS this year pointed out that the survey fails to measure far more crimes than it accounts for. For example, it does not include offences against children, a big omission since police figures show 29% of mugging victims last year were 11 to 16-year-olds. Nor does it measure rape and sexual assaults, which have risen every year since 2002.

More significantly, the survey does not measure murder, which many criminolo-gists believe gives the clearest signal of how violent a society really is.

A new report by the CCJS also shows that knives are now used in one in five muggings, twice the frequency reported two years ago. Attacks in which a knife was used during a street robbery rose from 25,500 in 2005 to 64,000 - the equivalent of 175 a day - in the year to April 2007, an increase of 151%.

A European Union crime and safety survey recently named the UK as a “high crime country” where the risk of becoming a victim was the highest in the EU except for Ireland. Britain spends more on criminal justice that any other western country, but the EU found “there has not been a significant step change” in outcome.

What can be done? For the Tories, the panacea is not more Asbos but, as David Davis, their home affairs spokesman, puts it, “proper, conventional policing and lots of it”. He points to the dramatic fall in crime in New York, which has 37,000 police officers compared with London’s 31,000. But the real difference is that the New York police department fields 40% more officers on the street.

Our attitude to teenage drinking may also play a role. After Newlove’s murder, Cheshire’s chief constable, Peter Fahy, called for the legal age for drinking to be raised to 21. Meg Hillier, the junior Home Office minister, ruled that out, blaming the drunken antics of celebrities such as Charlotte Church for setting a bad example.

Whitehall officials indicated that ministers would move to curb the availability of cheap alcohol in supermarkets and would look again at “happy hour” discounts.

The bigger question is whether better policing and government policies alone can really make an impact. “Parents should be the key to tackling this problem,” said Fahy.

Catlow, beaten to the brink of death, does not regret his actions. “I acted on the spur of the moment and I still think I did the right thing,” he said. “If I hadn’t stepped in they could have caused a crash.”

The yobs have not been punished. Shortly after the incident the police arrested four 15-year-olds on suspicion of causing actual bodily harm. The case was dropped before it went to court, however, after a key witness changed his story.

Catlow’s wife, Carolyn, who saw the youths running away laughing from his prone body, said: “I’m proud of him. Someone has to take a stand at times like that or the problem will just get worse.”

Additional reporting: Laura Pitel

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