Huntley was hired despite prior accusations against him

Information Commissioner Richard Thomas, an independent data protection monitor, said the police's decision had nothing to do with data protection.

The Bichard Inquiry is examining how Huntley, who killed two girls, had been cleared to work at a school.

It will hear from the chief constable of the force next week.

Data protection

After Huntley was convicted of killing 10-year-olds Holly Wells and Jessica Chapman, it emerged he had previously faced four allegations of rape and one of indecent assault on an 11-year-old girl, all in Humberside.

However the police force deleted the information from a police database.

So when police in Cambridgeshire ran checks on him after he applied to become a school caretaker, they found nothing.

There was nothing in the Data Protection Act from which Humberside Police could reasonably infer or conclude that they were required to delete intelligence information on Ian Huntley Richard Thomas Information Commissioner

Humberside chief constable David Westwood claimed his force thought they were required to delete details of the previous allegations under the terms of the Data Protection Act.

He is likely to appear at the inquiry next week, a list of witnesses released on Tuesday showed.

Giving his evidence in a written submission, Mr Thomas said: "There was nothing in the Data Protection Act itself, in the Association of Chief Police Officers code or in the guidance from my office from which Humberside Police could reasonably infer or conclude that they were required to delete intelligence information on Ian Huntley within a very short timescale.

"I do not put myself forward as an expert in such matters but the information that was deleted from the Humberside criminal intelligence system appears to be of such obvious value for the prevention and detection of crime that I find the decision to delete to be astonishing."

He said the Data Protection Act "does not stand in the way" of keeping information for some time on individuals to see if it forms a pattern.

'Weeding out'

And he said Humberside's policy of "weeding out" criminal files was "out of step" with the practice of other forces.

However, chief police officers blamed the information commissioner's office for "compounding" confusion on the issue.

"The information commissioner wants less offence details recorded on the Police National Computer, not more," said the Association of Chief Police Officers (Acpo).

The organisation gave an example to the inquiry of a suspect who was alleged to have committed two sex offences with boys in 1991 and 1998. He was arrested but no charges were brought.

Acpo said the retention of that intelligence had been questioned by the information commissioner.

In a statement, Acpo said it would like all criminal convictions to be held on the Police National Computer until the offender is dead or 100.

At the moment, only serious offences are held for that length of time.

The organisation said the details should be available for employment vetting.

The inquiry has already had evidence from organisations including the Home Office, the Police Federation, the Law Society and the civil rights group, Liberty.

Submissions have also been received from Cambridgeshire and Humberside Police.

The inquiry is expected to last until 30 March.