British society no longer trusts adults to interact with children. Since 2002, growing numbers of people have found themselves required to undergo a Criminal Records Bureau (CRB) check simply because their work or voluntary activities bring them into contact with children. This includes football coaches, cricket umpires, Guiders and Scoutmasters, volunteers in churches, charities and community centres, parents who volunteer for school trips or after-school clubs, and members of parent-teacher associations - as well as a host of others whose work is not to do with children, but might just involve having contact with them, such as bus drivers, or plumbers who fix school radiators. This month the BBC calculated that one in four adults will have to register with the new Independent Safeguarding Authority next year. The ISA boasts that something like 11.3 million people will be affected by the new scheme for vetting adults.

In the report Licensed to Hug, published on 26 June, my co-author Jennie Bristow and I explore the implication of the steady expansion of criminal-record checks on intergenerational relations and community life. What we found is that the system of vetting adults has taken on a bizarre life of its own. Already the question "Have you been CRB-checked?" has become part of everyday discussion at the school gates. We have talked to parents who were told that they could not attend their children's disco because they were not CRB-checked. Suspicion of grown-up behaviour towards children has fostered a climate in which it has become normal for some parents to trust only adults who possess official clearance. As one manager of a children's football team stated, "I only allow CRB'd parents to drive team members to training."

The research for Licensed to Hug indicates that most of our respondents in the voluntary sector accepted that a system of national vetting was now a fact of life. Many prefaced their statement with the word "unfortunately". Some were sceptical about its efficacy; others felt that it was burdensome and confusing. There were complaints about the enormous costs of maintaining the system and the amount of time it takes to process the paperwork. A significant minority of volunteers have been put off from working with children. One volunteer manager of an under-13s cricket team told us of his frustration at losing his "inspiring" coach who simply got "fed up with the hassle and paperwork".

Supporters of the new culture of vetting grown-ups argue that, whatever the critics say, the system protects children from adult predators. However, our experience of vetting as a society raises a question mark over the idea that the system "works", either in terms of protecting children from abuse, or in terms of increasing public confidence in those working or volunteering with children. As the recent history of the Criminal Records Bureau has shown, the first consequence of more stringent vetting procedures has been a demand for even more stringent security procedures. This indicates that the effect of CRB checks is less to increase trust in those organisations and institutions that insist upon vetting than it is to fuel mistrust in those that do not.

Experience indicates that the institutionalisation of the vetting of adults has unleashed a logic towards increasing the number of people who are deemed to be in need of formal clearance. So, in February 2008, the government announced trials of a new scheme that would enable parents to check with police whether a '"named individual" - a family member, a neighbour who looks after children, a new sexual partner - has child sex convictions. The Home Secretary, Jacqui Smith, stressed that the initiative would not be a "community-wide disclosure", with information given out to anyone who asks. The more this process goes on, however, the more arbitrary it becomes to say where vetting should stop and trust begin.

The alleged protective effects of a system of vetting are largely illusory. Aside from the fallibility of record-keeping and technical systems, vetting takes into account only what somebody has done in the past. The most sophisticated system in the world cannot anticipate how individuals with a clean record might behave. Thus, the CRB provides little guidance about people's behaviour in the future. It provides the impression of security, but not the substance. It is difficult to avoid the conclusion that the national vetting scheme represents an exercise in impression management rather than offering effective protection. Vetting measures also fuel suspicion about adults. In that sense, they are not just harmless rituals, but negatively influence the conduct of adult-child relationships.

Although proponents of the scheme contend that it is designed to prevent "worst-case scenarios", the very institutionalisation of the scheme encourages worst-case-scenario assumptions to become the norm. One consequence of this process is that adults feel increasingly nervous around children, unwilling and unable to exercise their authority and play a positive role in children's lives. Such intergenerational unease has not made children safer than in the past: if anything, it is creating the conditions for greater harm, as adults lose the nerve and will to look out for any child who is not their own. Perversely, it inadvertently encourages grown-ups to avoid their responsibility for assuring the well-being of children in their community. One of the principal consequences of the vetting of grown-ups is the legitimisation of the idea that it is not the responsibility of the older generation to take a direct interest in the lives of children.

The most regrettable outcome of the new child protection policies associated with vetting is the distancing of intergenerational relationships. They foster a climate where adults feel uneasy about acting on their healthy intuition and feel forced to weigh up whether, and how, to interact with a child. Such calculated behaviour alters the quality of that interaction. It no longer represents an act founded on doing what a mentor feels is right - it is an act influenced by calculations about how it will be interpreted by others, and by anxieties that it should not be misinterpreted.

In sport, the difference between a coach automatically reaching out to correct a child's position and a coach asking himself, "Is this all right?" before doing so is that the former is a spontaneous action based on a desire to improve the child's game, and the latter is a timid gesture, reflecting an uncertainty about authority that the child must surely sense. In a community group, the difference between giving a distressed child a hug and asking that child, "Would you like a hug?" is that the former is given as an unprompted expression of human compassion, and the latter is a transaction that requires a child's formal consent.

Without doubt, children need to be protected from those who may prey upon them. However, the policing and formalisation of intergenerational relations does little to help this. The policy of attempting to prevent paedophiles from getting in contact with children through a mass system of vetting may well unintentionally make the situation more complicated. One regrettable outcome of such policies is the estrangement of children from all adults - the very people who are likely to protect them from paedophiles and other dangers that they may face. The adult qualities of spontaneous compassion and commitment are far more effective safeguarding methods than pieces of paper that promote the messages: "Keep out" and "Watch your back".

Adults feel at a loss

During the course of our discussions with people working in the voluntary sector, it became evident that applying formal procedures to the conduct of human relations also threatens to deskill adults. Many adults often feel at a loss about how they should relate to youngsters who are not their children. When formal rules replace compassion and initiative, adults become discouraged from developing the kind of skills that help them relate to and interact and socialise with children. This process of deskilling the exercise of adult authority may have the unfortunate consequence of diminishing the sense of responsibility that adults bear for the socialisation of the younger generation. Individuals who talked to us about the "hassle of paperwork" also hinted that they were not sure that working with kids was "worth the effort". And if adults are not trusted to be near children, is it any surprise that at least some of them draw the conclusion that they are really not expected to take responsibility for the well-being of children in their community?

Most policymakers, as well as thinking adults, do sense that there is something wrong with the conduct of intergenerational interaction. Of course, the crisis of intergenerational trust is a complex cultural problem, to which there are no quick fixes. It would be one-sided to argue that policy developments such as the national vetting and barring scheme have created this problem, and that removing them would solve things overnight. However, our research suggests that the creation of a probationary licence for adults through the national vetting scheme exacerbates the breakdown of trust within communities, and throws assumptions about adult authority and responsibility into question in a way that militates against people stepping in to help children out when things go wrong.

What is needed is both enlightened policy, which puts greater trust in the ability of professionals and volunteers to act on their instincts and less pressure upon them to cover their backs; and less policy: putting a halt to the juggernaut of regulation and behaviour codes that makes voluntary organisations increasingly difficult to run, and volunteers resentful and unsure of themselves. As the government evaluates its national vetting scheme, we suggest that it pays at least as much attention to the consequences in terms of deterring "good" volunteers as it does to the scheme's effectiveness in keeping "bad" volunteers out.

However, the single most important problem that needs to be addressed is how society can affirm and support the exercise of adult authority through acts of solidarity and collaboration.

The growing distancing of encounters between the different generations in our society can only be fixed through providing adults with greater opportunity to interact with children. Adults need to be encouraged to exercise their responsibility towards the guiding and socialising of young people. That means that we need to question and challenge cultural assumptions that automatically throw suspicion on adults and the exercise of adult authority.

Frank Furedi is professor of sociology at the University of Kent. Jennie Bristow is a journalist and the mother of two pre-school girls

"Licensed to Hug" is published by Civitas (£5)