The BBC's Peter Gould: Hindley may take campaign to the Lords

Her lawyers have gone to the Court of Appeal in the latest stage of her campaign to secure her release.

After considering legal arguments, three senior judges including the Master of the Rolls, Lord Woolf, will give their decision.

Whatever they decide, the legal arguments are certain to continue, and the issue could go to the House of Lords.

Public outrage over Hindley, 30 years on

Presenting Hindley's case last month, her barrister, Edward Fitzgerald QC, said she had been singled out for unfair treatment because of her "notoriety and unpopularity".

Just as she thought she was nearing the end of her sentence, after serving 32 years, she was told that she was being placed in a category of prisoners for whom life really would mean life.

Peter Gould: "Hindley could spend 70 or 80 years in prison before she dies"

But lawyers for Mr Straw argued that killers like Hindley should never be released.

They urged appeal judges to uphold last December's landmark decision by three High Court judges that 'whole life tariffs' were lawful, provided prisoners could still be released in "exceptional circumstances".

Brady denies threatening Hindley

Myra Hindley was convicted in May 1966, along with Ian Brady, of the murders of Lesley Ann Downey, 10, and Edward Evans, 17.

Brady was additionally convicted for life for murdering 12-year-old John Kilbride.

Both later confessed to the further killings of Pauline Reade, 16, and Keith Bennett, 12, burying their bodies on Saddleworth Moor on the edge of the Peak District.

The 'life means life' tariff was first imposed on Hindley in 1990 by the then Home Secretary David Waddington.

The decision was confirmed by his successor Michael Howard and approved by Mr Straw last November.

Arguing in the Appeal Court, Mr Fitzgerald said the decision failed to take into account the lesser role Hindley had played in the murders.

He said she been corrupted by Ian Brady and had only gone along with him after he threatened her.

Lord Longford, a long-time campaigner for Hindley's release, has insisted that she has made excellent progress in prison and become "a good woman".