HUNDREDS of blacklisted teachers, including paedophiles, are being allowed into schools so long as they avoid certain types of pupils, The Times has learnt.

Headteachers are having to accept supply staff into classrooms without knowing if they are on the blacklist or have criminal records.

As a picture emerges of a child protection system in chaos, the Government is preparing to strip ministers of their power to let sex offenders work with children. Police will receive a new advisory role.

The practice of giving convicted paedophiles permission to work in schools with pupils of a different age or sex from those they desire was disclosed by The Times this weekend.

Yesterday a former teaching agency official who had access to List 99 confirmed that this procedure was widely known among companies providing supply teachers. Yet it appears to have come as a surprise to teachers’ leaders and parents.

There are about 15,000 on the blacklist compiled at the Department for Education and Skills (DfES). Gerard Connolly, who held the names of all problem teachers on a computer in his office from 1996 to 2004, said that many had “caveats”.

Most forbade teachers from working with one gender of pupil, or children above or below a particular age. Some had geographical restrictions placed upon them. A few were banned from individual schools.

“You used to see them every other page or so with a restriction on,” Dr Connolly said. He estimated that between 700 and 1,000 names on the blacklist had permission to teach particular categories of pupil.

“I have no way of knowing how many were working in schools but they were certainly free to do so,” he said.

Last night an Education Department spokesman said: “The list is held by the department and the criminal records bureau. We certainly don’t recognise that figure.”

Dr Connolly was puzzled by the Government’s delay in telling the public about the number of sex offenders who are entitled to work in classrooms. “It surprised me, people coming on television saying they don’t know,” he said. “All they have to do is count them.”

The unexpected scale of the problem added to the woes of the DfES, which has struggled to keep up with the pace of disclosures about paedophile teachers. Ruth Kelly told the Commons last Thursday: “List 99 covers those barred for life from working in schools.”

On Friday her officials were still claiming that List 99 was an “absolute bar” on teaching. Then The Times reported that in 2001 Estelle Morris had allowed Keith Hudson — who was placed on the sex offenders register after compiling scrapbooks containing pictures of boys masturbating — to work in girls’ schools. A convicted molester who was fixated on boys in white underpants has permission to work with children aged 14 and over. Both are on List 99.

Officials changed their story. A spokesman said: “In 2000 we introduced regulations to make sure that barring someone convicted of sexual offences against a child was absolute.”

But that explanation imploded yesterday when it emerged that in January 2005 Ms Kelly allowed William Gibson to work in schools. He had a conviction for indecently assaulting a 15-year-old female pupil. Mr Gibson’s case highlights that teacher-supply agencies are a weak link in child protection. After being removed from three schools in the North East he found a position teaching mathematics in Bournemouth.

The job came via Step Teachers, an agency aware of his conviction in 1980 for indecent assault and his imprisonment in 2000 for deception, forgery and theft. Mr Gibson has been suspended. James Newman, the agency’s director, said: “Step Teachers undertakes not to discriminate against an application on the basis of a conviction or other information. It is unfortunate that the teacher is still very much in shock over the circumstances and the way he is being treated.”

The agency had provided Mr Gibson without alerting the head that he was a convicted child molester. Agencies bear responsibility for checks of criminal records and List 99 entries. Step Teachers claimed it was forbidden from telling schools about convictions. “Under the terms of the agreement with the Criminal Records Bureau, we would not be able to tell the school,” Mr Newman said. “We would have to destroy all that documentation because of data protection laws.”

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