CRIME is very much on the minds of York people. That came home to Liberal Democrat activists during the General Election campaign.

Residents' concerns about vandalism, burglary and anti-social behaviour were made clear time and again on the doorstep, and confirmed by the Lib Dems' own survey.

The fears are greatest on what are known as "York's troubled estates". Despite the best efforts of most law-abiding residents, lawless yobs still target these estates. They can only reclaim their good name when the offending is stopped.

The Lib Dems' big idea is to bring Neighbourhood Watch out from behind the net curtains and put it onto the streets. Neighbourhood wardens would patrol the area gathering information on crime for the police.

In theory, this scheme has obvious attractions. The police do not have the resources to walk the streets around the clock, and they depend heavily on evidence from residents to bring the street criminals to book. By actively seeking that evidence, neighbourhood wardens might help to detect crime and to deter it.

In practice, however, the scheme raises obvious doubts. There must be a question as to whether the Lib Dems would find enough people willing to take part.

Wardens would need to devote a great deal of their time to their patrols. And this would be unpleasant work which could bring them into direct conflict with their most aggressive neighbours.

Here is the scheme's biggest drawback. Neighbourhood wardens would become the yobs' main target. As a result, the wardens might be tempted to go beyond their passive detection role and take direct action to "sort out" the offenders. This is called vigilantism, and it can inflame the problems.

It is always worthwhile to look for ways in which a community can solve its own problems. But there is a thin line between public-spirited vigilance and ham-fisted vigilantism.

In their discussions with our crime detection professionals, the police, the Liberal Democrats must listen carefully.

Updated: 10:31 Monday, June 25, 2001