Questions were raised inside Broadmoor, the high-security psychiatric complex where staff laughed about Mr Savile's psychopathic tendencies and where paedophiles gravitated toward him.

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Channel 4 News spoke to staff who worked at Broadmoor 24 years ago when staff said Mr Savile roamed the corridors with a set of keys and the freedom to go anywhere. He mingled repeatedly with the 800 or so patients, many teenage girls, some severely disturbed and medicated.

Jimmy Savile was one of Britain's biggest stars during the 1960s and 1970s - and, allegedly, one of its worst sexual predators. He started out as a dance hall DJ, then in the early 1960s he hosted the music programme Top of the Pops and later "Jim'll Fix It," a TV show in which he made young viewers' wishes come true. But Broadmoor staff considered him a psychopath.

"I'd long considered him, as did my colleagues did, as a man with a severe personality disorder and a liking for children," Richard Harrison, a psychiatric nurse at Broadmoor for 30 years during Savile's tenure told Channel 4 News.

Paedophiles were drawn to him

Talk about the entertainer being a paedophile was common among staff and paedophile patients - who gravitated toward him - staff said. But Jimmy Savile lived in an era of social transformation. He was not charged or put on trial during his lifetime and died a year ago, two days short of his 85th birthday.

"I'd say he was a psychopath," said Bob Allen, a staff nurse at the time. "A lot of the staff said he should be behind bars. We used to laugh about it in those days."

Mr Allen described one evening when he saw the BBC entertainer in a car with a young girl who appeared to be 14 or 15 years old. Savile and the girl went into the flat the star had been given to use at Broadmoor. As Mr Allen walked away, the lights in the flat dimmed but nobody came out. He said he reported it to his supervisor, who he believes did refer the matter up, but was told the following day that "no one appears to be interested."

Considered a flamboyant character, hopping around, flirting with patients and acting in an off-the-wall manner, Jimmy Savile's celebrity dazzled and silenced, staff said. And he was not just a visitor, for a time he was in charge. In 1988, Health Minister Edwina Currie appointed Savile to head up a task force to run the hospital.

The lunatics are in charge

The response from staff? "The lunatics have taken over the asylum."

But at the time, it was also a period of change where the old, grim Victorian accommodation was trying to upgrade and improve care for the mentally ill. Mr Savile was given extraordinary power and a set of keys with complete access to every part of the hospital, the staff told Channel 4 News.

The Ministry of Health said Savile was made chairman of the task force in a move to liberate the culture. With his gold tracksuits, big cigars and jocular persona some thought he was a harmless eccentric. Broadmoor staff may have had a different opinion but not much appears to have been done about it.

In one particularly unnerving incident, Mr Savile told staff to supply disturbed, medicated patients with a drink at Christmas, despite their doctors' orders. Mr Savile then left the ward and returned 30 minutes later with beer, Mr Harrison said.

"The consultant, when he discovered what he had done, was furious," Mr Harrison said.

Savile help appointed new chief executive

Mr Savile's task force ran the Broadmoor for 15 months and the disc jockey continued to have a power in its management after that. He was involved in the appointment of Alan Franey as new chief executive - a friend of Savile's from Leeds who ran the marathon with him.

According to the staff, they felt their concerns had been raised about the appropriateness of Mr Savile's presence and power at the hospital. As far as they were concerned, there was nothing more they could do.

Since allegations about Savile were broadcast in an ITV documentary several weeks ago, some 300 alleged victims have come forward saying they were abused by the entertainer in various places, including BBC dressing rooms and the hospitals he visited.

Officers now investigating the allegations have said that the Savile case will be a watershed moment in combating child abuse, but for the patients of Broadmoor, it will be too little, too late.