The authorities in Grimsby knew a lot about Ian Huntley.
By Niall Dickson
BBC Social Affairs Editor
From the mid 1990s he targeted young girls - yet they never had enough evidence to stop him.
Social services looked into four separate complaints he had sex with underage girls - one was just 13 - and an allegation of indecent assault on a 10-year-old.
Huntley was charged with a rape in Grimsby but the case collapsed
The police were involved in all but one of these cases and also investigated three separate claims by women who said Huntley had raped them.
He was also charged with a burglary, although the case was dropped when it came to court.
In spite of all this, Huntley emerged without a conviction - only the burglary charge was placed on the police national computer and that was on the orders of a judge.
PREVIOUS ALLEGATIONS AGAINST IAN HUNTLEY
One of indecent assault
Four of underage sex
Three of rape - one resulted in a charge
The first of many questions is whether the authorities in Grimsby could have done more to halt Huntley's offending behaviour.
Social services never linked the cases together. North East Lincolnshire council say this was because the five cases were handled by four different teams of social workers operating in different parts of Grimsby and that their files are concerned with victims not perpetrators.
They also point out that in every case bar one the police were also involved.
"Huntley was never convicted of any crime," said Jim Leivers from North East Lincolnshire Council.
"Clearly there were investigations into alleged crimes that Huntley was involved with but decisions were taken not to proceed with those cases for various reasons.
"Those were decisions that the police took."
However social services are the lead child protection agency and Grimsby is not a huge place.
The council now has a single system of referrals which might have picked up Huntley's role at least in the three cases that were referred in March, April and May 1996.
Check system failed
The Humberside police role will certainly come under even greater scrutiny.
It seems as if, because of the way the force failed to retain intelligence, officers interviewed Huntley on a number of occasions without realising he had a string of past allegations against him.
But perhaps the most critical question is how was Huntley allowed to become a school caretaker?
Huntley applied for the Soham job under the name "Ian Nixon"
There is supposed to be a thorough system of police checks to prevent anyone unsuitable from working with children - there was a mass of evidence that Huntley was a menace, yet he was given the all clear.
By the time he applied for the job at Soham, Huntley had changed his name to Ian Nixon - that might have fooled the system but in fact he did admit his original name was Huntley.
His police checks form first went to the Cambridgeshire force - they checked the police national computer under the name Nixon but they failed to check under Huntley - which would have thrown up his burglary charge.
Cambridgeshire Chief Constable Tom Lloyd admits that this was a mistake.
Soham Village College head teacher Howard Gilbert says Huntley would not have been given the position of caretaker if the school had known about the burglary charge, not least because security was on the first line of the job description.
The school would not have taken the risk of employing a caretaker with an unresolved burglary charge.
Mr Gilbert said he felt "physically sick" that the allegations of underage sex and indecent assault were not passed on to him.
Huntley had a string of allegations of sex assaults in the 1990s
He added: "It's got to change. I understand that there's a civil liberties side as well and we can't set a system up where a malicious allegation could lead to somebody's career being blighted.
"But also we've got to protect children"
But the Cambridgeshire mistake pales into insignificance alongside those of Humberside police where all the local intelligence should have been stored.
The Humberside force believes their colleagues in Cambridgeshire only sent them the name Nixon, but that should not have mattered.
On two occasions Humberside officers were told Huntley and Nixon were one and the same - but they failed to record this on their files.
What is more, the entire Humberside intelligence system was seriously flawed - vital information on suspects was routinely thrown away because senior officers misinterpreted the Data Protection Act.
And, most incredible of all, the staff in Humberside police responsible for vetting job applicants such as Huntley were not able to access a database with information about sex offences and children.
This case has exposed a catalogue of errors as well as fatal flaws in procedures and systems.
An inquiry announced by the home secretary will now have to establish what went so badly wrong that this dangerous man was allowed to work in a position of trust with children.
In schools and other institutions working with children there will be real concern that the checking system failed so badly.
Among those directly involved there will be anger and dismay.