The government has announced it will review its plans to introduce vetting of adults who take part in activities involving regular contact with children following strong criticism.
Under the planned rules, adults in England and Wales who take part in any formal agreement to look after children - even if it is as little as once a month - will have to register with the new Independent Safeguarding Authority (ISA). Registration will cost £64 in England and Wales, but unpaid volunteers will be exempt from the charge. From next summer, adults who have failed to register with the ISA could face prosecution.
Critics of the scheme, including Esther Rantzen, the founder of the Childline charity, are concerned that the new scheme will deter adults from volunteering with children's organisations and create a climate of paranoia.
Esther Rantzen said: "This is less about protecting children than about organisations protecting themselves. Of course we need to be alert to the safety of our children. We don't want a convicted child abuser taking a job as a tennis coach, a youth worker or a police officer. But we have to be sensible about this and I don't think we are."
Nick Clegg, the Liberal Democrat leader, said: "This scheme is wildly over the top. How are we supposed to create a country fit for our children if we regard every adult looking after children as a potential threat?"
The Conservatives have pledged to curb the ISA's powers if they win the next election.
In addition some leading children's authors - including Quentin Blake, Philip Pullman and Anthony Horowitz - have pledged to stop giving readings at schools if the new scheme is introduced.
The head of the ISA has responded by telling the critics to "calm down". Sir Roger Singleton said: "We need to calm down and consider carefully and rationally what this scheme is and is not about."
"It is about ensuring that those people who have already been dismissed by their employers for inappropriate behaviour with children do not simply up sticks and move elsewhere in the country to continue their abuse.
"It is about giving parents confidence that there is no known reason why those caring for their children are unsuitable because of their previous misbehaviour," Sir Roger said.
"And it is about bringing an end to the need for repeated criminal record bureau checks which so many people have found irritating. ISA registration is a one-off process for a single fee. The Vetting and Barring Scheme is a significant development which should be debated on the facts and not on myths and inaccuracies."
However, today the Children's secretary Ed Balls announced a review of the scheme in a letter to Barry Sheerman, chair of the children, schools and families select committee. Mr Balls said he had asked Mr Singleton to examine whether the government had got the balance right in defining what activities should and should not be covered by the scheme.
Sir Singleton has been asked to report back by the beginning of December.