Patrols of former violent criminals paid to walk the streets are being welcomed by people in high-crime areas, criminologists have found.
The first academic study of a vigilante-style crime-fighting scheme showed that residents were reassured by the knowledge that burglars would be up against local hardmen.
An elderly woman, who pays £1 a week to a street patrol, told researchers: "If one criminal group knows another criminal group is protecting an area then they'll be put off going into that area.
"They're not so worried - the criminals - about the law, but if they go into another criminal's patch there will be repercussions."
The study, in this month's The Howard Journal, an influential periodical on criminal justice issues, will have significant implications for the Government's plans later this summer to regulate the private security industry. Ministers intend to ban people with convictions for violent crime being licensed to work as private security guards.
The researchers focused on a commercial street patrol in a deprived district of Doncaster, South Yorkshire, where for seven years a former prize-fighter with a string of criminal convictions has been offering his security services.
Malcolm Tetley has 25 convictions, including burglary and assaulting a police officer, and has served several jail terms. He became a Jehovah's Witness but regards his criminal past as a positive asset when it comes to promoting the services of his company, Household Security. He told researchers: "We live in a system where the fist matters. There's only one person who can do this job and that's a villain. They have great respect for that person in these areas, and the people in the housing estates will know this, and they will be left alone."
The report's authors, David Wilson, a professor of criminal justice, and Douglas Sharp, a former police officer who is now a senior lecturer at the University of Central England, found that Mr Tetley's paying customers took the same view. One said: "The police hands are tied - they're frightened to wave the big stick. With these people, for a small amount of money, they'll wave the big stick."
The report found: "It is clear that Household Security had indeed tapped into a local feeling of insecurity and disenchantment with the formal agents of policing, and that Malcolm Tetley's history of criminal offences, far from putting people off the business, had become a positive boon."
Mr Tetley admitted that he was happy to employ other peoplewho had a record of violence, although he added: "Not that I want them to knock people about."
Household Security patrols streets by foot and by van. Customers are given a sticker to display at the front of the house and a torch is shone on their windows at night to let them know that they have been visited.
One 85-year-old woman customer said: "I don't get out now and there's hardly anyone I know living in this street. I get peace of mind. Household Security comes round, and when you're living on your own and have their phone number, it gives you peace of mind."
But Mr Tetley's activities have aroused deep suspicion in the local police force, which he blames for the decline of his business in recent years.
Senior officers have accused him of pandering unduly to people's fears, questioned his competence, and warned of the dangers of people taking the law into their own hands.
The research report concludes that the public demand for a security service which does not conform to formal models of policing and private security, creates a dilemma for policy-makers, whose proposals for regulating the system would make Mr Tetley's activities illegal. It states: "There is a clear sense that customers of Household Security employed the firm precisely because they believed it operated outside of the law."
Last night, Mr Tetley, who is off work after an accident, said he hoped one day to employ "ex-villains all over the country, in their own areas, who have got the same respect as I have in my area. Then crime will stop".