Her legal team are fighting a ruling by British Home Secretary, Jack Straw, that she will spend the rest of her life in prison.

She has already served 31 years for her part in the murder of Lesley-Ann Downey, 10, and Edward Evans, 17. Her accomplice, Ian Brady, was also convicted of the murder of schoolboy, John Kilbride, who went missing from a market in Ashton-Under-Lyme, near Manchester.

They became known as the Moors murders because the victims' bodies were buried on Saddleworth Moor, near Manchester.

Her QC, Edward Fitzgerald, has appealed to the Lord Chief Justice, Lord Bingham, and two other senior judges to overturn a series of rulings that her life sentence "will mean life".

He argued that the time she had already served was sufficient "to meet the needs of retribution and deterrence" and she was now entitled to be considered for parole.

The High Court in London is hearing why life should not mean life for Hindley

Her minimum sentence, or "tariff" for retribution and deterrence, was provisionally set at 30 years in 1985 by the then Home Secretary, Leon Brittan. It was increased to "whole life" in 1990.

The current Home Secretary recently agreed that Hindley, 55, who was not in court for the hearing, must die in jail.

Hindley and Brady are the only lifers to have had their tariffs increased, and Rose West, convicted in 1995 of the murders of 10 females, is the only other woman to receive a whole life tariff.

Mr Fitzgerald told the judges: "This is the only case where someone has received a whole life tariff who was not the actual killer themselves."

He also argued that the whole life tariff failed to differentiate between the culpability of Hindley and her co-defendant, Brady, "despite the clear distinction drawn by the Crown, the judiciary and the police".

The main argument advanced on Hindley's behalf was that she "had acted throughout under the influence of threats and intimidation by Brady".

Mr Fitzgerald said that during the 1966 trial, the Crown had acknowledged that Hindley had been "indoctrinated" by Brady and that he had both initiated and planned the crimes in which she participated.

He said: "The jury reflected the view that Myra Hindley became involved as a secondary party after Brady had started the killings by acquitting her of the first of the murders, that of John Kilbride.

"Though she has subsequently - and to her credit - admitted her part in the prelude to John Kilbride's death, the jury's verdict does reflect the wider reality that Brady was the initiator of all the crimes."

Mr Fitzgerald said that after the trial, the judge wrote a confidential letter to the then Home Secretary which did make a distinction between Hindley and Brady.

He wrote: "Though I believe that Brady is wicked beyond belief without hope of redemption (short of a miracle), I cannot feel the same is necessarily true of Hindley once she is removed from his influence.

"I hope Brady will not be released in any foreseeable future (assuming his fellow prisoners allow him to live) and that Hindley (apart from some dramatic conversion) will be kept in prison for a very long time."