A perverted teacher was cleared to work in a Brighton school despite being accused of "grooming" a 14-year-old girl over the internet weeks earlier.

Nigel Jackson, 48, was free to walk into a job at East Brighton College of Media Arts (Comart) within a month of quitting a post in a neighbouring authority amid warnings he could be a risk to children.

Jackson was dismissed from Comart and escorted from the premises as soon as the school obtained his references but he was then hired to teach in at least two other Sussex schools.

He was cleared to work in the schools after warnings had also been sent to the Department for Education and Skills (DfES).

This was a full year before he admitted grooming another 14-year-old girl for sex in Northern Ireland. He was able to indecently assault the girl there despite an earlier investigation by Sussex authorities.

On Monday, Jackson admitted to courting a schoolgirl in Ireland via the internet, indecently assaulting her and inciting her to commit acts of gross indecency at Londonderry Crown Court.

The Argus today reveals that a letter suggesting Jackson should be barred from working with children was sent by East Sussex County Council within a month of him leaving his post over allegations of inappropriate behaviour towards a teenage girl in Sussex in January 2004. During the same month, he walked into a job at Comart and, after being marched off the school, he went on to work at Littlehampton Community School and Durrington High School in West Sussex.

The parents of the Sussex girl say they are distraught that Jackson, who was deputy head at Seaford Head Community College until January 2004, was allowed to continue teaching after the previous allegations.

The girl's father said: "We feel very angry. The system has failed us. We thought the whole thing was finished. We feel awful the same situation has happened to another girl."

East Worthing and Shoreham MP Tim Loughton, the shadow children's minister, pledged to raise the case when Ruth Kelly reports to Parliament tomorrow.

He said: "This is exceedingly worrying. A man like this has no place working with children.

"There is currently a great deal of confusion over who is responsible for making sure individuals with a known record or with question marks against them are not allowed to work with vulnerable people."

Jackson, 48, of Bowden Rise, Seaford, left the college in Steyne Road amid a police investigation into his behaviour towards the 14-year-old.

It is alleged Jackson later contacted the girl using instant messaging - posing as a 15-year-old boy - and continued to email and court her for three months.

When the girl's parents realised what was happening, they alerted the authorities, a police investigation was launched and they were told Jackson would be registered on List 99 and banned from teaching.

Jackson was never prosecuted but East Sussex County Council referred his case to the DfES in February 2004 outlining its concerns.

List 99 is the DfES blacklist of people banned or restricted from working with children. It covers sexual offences and crimes of dishonesty or violence. People are automatically registered if they are convicted of an offence but the DfES can include others if there is evidence to do so.

Despite the request from East Sussex to have Jackson banned from teaching, he took up a new post at Comart later that month and found employment at two schools in West Sussex until as late as April last year - even though West Sussex County Council knew of the concerns.

Jackson's offences in Northern Ireland took place between March 1, 2004 and April 23, 2005 and did not involve any children from Sussex.

Karen Lees, who was the headteacher of Comart at the time of Jackson's employment in February 2004, said Jackson wrote to the school asking for supply work and was taken on subject to his references being checked.

She said he worked at the school for up to two weeks but was dismissed and escorted from the premises when references from East Sussex County Council revealed serious concerns about his suitability to work with children.

She said it was not clear if Jackson was actually on List 99. She said: "I got the idea it was pending and likely."

Jackson then registered with agency Teaching Personnel which found work for him at Littlehampton Community School and Durrington High School in West Sussex.

He spent four days in Littlehampton in 2004 and a few days at Durrington High the same year.

From January until April 2005, Jackson was back at Durrington when the agency and authorities were alerted to the police investigation in Northern Ireland. He was suspended from teaching immediately and local teaching agencies were alerted.

Mark Dunn, the cabinet member for children's services, said: "In these circumstances, where people are intentionally trying to get under our guard it's very difficult to stop them unless everybody is fully alert.

"We are obviously taking steps to make sure our system is foolproof."

According to a spokeswoman for West Sussex, the council received information on Jackson from East Sussex in July 2004 but was not obliged to pass this on to teaching agencies.

She said agencies were expected to conduct their own checks and there had been no complaints made against Jackson in West Sussex.

Teaching Personnel director Mark Weavis said Jackson worked in schools in both East Sussex and West Sussex from July 2004 until April 2005.

He said the agency performed and satisfied all its standard checks, including an enhanced Criminal Records Bureau check, List 99, qualifications, residency, identity, General Teaching Council registration and medical fitness.

He said: "Notably, our policy is to personally obtain the two most recent school references directly and, in Mr Jackson's case, these were returned as exemplary."

Matt Dunkley, director of children's services at East Sussex, said: "The recent situation highlights a serious need to review current national practice and legislation and we urge the minister to tighten existing laws as a matter of urgency."

A DfES spokesman said the Government did not comment on individual cases but Education Secretary Ruth Kelly had commissioned an urgent review.

Mr Loughton said: "Information about Jackson was available to the DfES and education authorities that he may not be appropriate to employ, yet he was given a job teaching children of my constituents.

"There is a concern that agencies are not as thoroughly scrutinised as LEAs and people like this are slipping through the net and that needs tightening."

Bognor and Littlehampton MP Nick Gibb, the shadow minister for schools, said: "This exposes huge question marks about why the information passed to the DfES was not acted on and why he was not put on List 99.

"The fact he was subsequently employed by a school in my constituency seems to be a system failure at West Sussex County Council, which did not pick up on the fact it were employing someone, albeit indirectly, about whom there were serious and highlighted misgivings.

"West Sussex County Council should conduct an internal inquiry into how this has been allowed to happen and I will be tabling a Parliamentary question to the minister."

Labour MP Des Turner, whose Brighton Kemptown constituency takes in Comart, said: "There is evidently a very unsatisfactory flaw in the system. If agencies insert teachers who have not been checked to the right standards then it undermines the protection.

"I hope and trust the review being undertaken by the DfES and reported tomorrow will take these factors into account because this must not be allowed to continue.

"I will certainly launch a personal investigation into this case."

Norman Baker, Lib Dem MP for Lewes, said: "East Sussex County Council acted properly by notifying the Government of its concerns but it only got a reply four months later .

"That is a dereliction of duty.

"Even more worrying is the fact East Sussex did the right thing in warning West Sussex and Brighton and Hove yet Jackson was still given employment.

"The DfES and councils need to ask themselves serious questions and I will be referring the matter to the minister."

Jackson was returned to custody after the hearing on Monday for psychiatric reports.

He has already signed the Sex Offenders Register and is due to be sentenced on February 24.