IN the depths of one quiet night, a long time ago, the night news editor of a Fleet Street paper discovered by accident an old unsealed envelope. He took it out of the newsdesk safe and opened it. Out fell a number of square black-and-white photographs, old-fashioned, with a broad white margin. Each showed a small girl, naked apart from shoes and socks, in various poses. She was gagged with a scarf. An accompanying note indicated these were the pictures of Lesley Ann Downey taken on Boxing Day 1962 by Myra Hindley and Ian Brady, minutes before they murdered her. The photos had been given to the paper's crime reporter, long dead. The man, stunned, simply put them back where he had found them.

Those pictures scalded him. They haunted him for 20 years and more. He never mentioned them to anyone. There are some nightmares you cannot share. The memory was jolted forcibly when he read a long article by Myra Hindley, published in the Guardian newspaper two years ago this month.

For Paul Donovan, its detached and anaesthetised tone was in stark contrast to the horror of her crimes. The only fingerprints found on those pornographic prints were Hindley's. Hers was the voice on the tape saying to a terrified child: ''Shut up or I'll hit you one.''

For the first time he told about his find in a letter to the newspaper. It was but one in a massive response from readers responding to Hindley's article. Almost all were in favour of Hindley remaining in prison. Many civilised, liberal people found to their astonishment that for once in their lives they supported Michael Howard in his insistence that she must spend the rest of her life in prison.

This week, before the Lord Chief Justice in the English High Court, Myra Hindley challenged the decision of the new Home Secretary, Jack Straw, that she would never be freed. Her lawyers argue that her proper tariff was 30 years which she has already served. They may well win the point because the House of Lords has limited the scope for Home Secretaries to vary sentences by ruling that the first sentence fixed by a Minister and communicated to the prisoner is the sentence they should serve. In 1985, the then Home Secretary Leon Brittan set a tariff at 30 years. Five years later another Home Secretary changed this to whole life. Hindley's crimes had not changed. But who would want to be remembered as the politician who released a Moors Murderer?

If the courts find that the goalposts on Hindley's sentence were unlawfully moved, Jack Straw may argue that he is entitled to keep Hindley in jail forever, because to release her would undermine public confidence in the criminal justice system. The courts would then have to judge what precisely the state of public opinion would be on this matter. That shouldn't be hard.

It has always been possible to detain a prisoner for life if the offender remains a danger to the public. Nearly 60 life-sentence prisoners have died in prison over the past five years. The longest-serving prisoner is John Straffen who has served 45 years for the murder of three children. There is no campaign for his release. Nor is there one for Hindley's accomplice Ian Brady. But Hindley is a woman.

Those who support her campaign for freedom say she is no longer a risk to society. They are probably right. She will not repeat her offences. Long-term prisoners can alter for many reasons: remorse, ageing, maturity, the influence of others, personal and spiritual change. In a civilised society, supporters argue, the denial of hope should not be absolute. So let's look back for a moment at the changing face of Myra Hindley.

For 20 of her 30 years in prison, Hindley denied her guilt. Then eight years ago she did, finally, admit to two further murders, of Keith Bennett and Pauline Reade. As late as July 1995, Hindley was complaining to the writer Linda Grant that she was a political prisoner. In a letter to Grant she made a surprising statement: ''I didn't kill anyone.'' What can this mean? On May 7, 1966 Myra Hindley was convicted of the murder of Edward Evans and Lesley Ann Downey. She was found to be an accessory to the murder of John Kilbride.

Or does she mean that she was involved only in the abduction and is not a killer? If so, she now sees herself as equally if not more culpable than Brady because, she argues, unlike him she was and is not mad.

The article she wrote for the Guardian in December 1995 was her opening shot in the campaign against the whole life tariff. It was full of insight and self-knowledge, described her loveless home life. It was all about Myra. It referred only briefly to what she calls her horrible crimes. She shed no light on why she committed them. There is no illumination of evil. Nothing to suggest she has spent her time behind bars considering anyone other than herself and her grievances.

Still, a nation which has discarded the barbarism of the death penalty needs to consider carefully how it can effect justice in cases which seem to go beyond our capacity for understanding evil. In hearts not filled with hate and unresolved anger, there is a recognition that justice is not revenge and is more than punishment. It is a desire to set the world back into moral balance.

Even if Hindley is not the same person who committed the Moors Murders, the murders stay done. None of us can shrug off our past, we are the consequence of all our actions. Hindley demands nothing less than her freedom. If she expects release, the least she can do is offer atonement.

Her greatest gift of repentance would be a treatise on depravity which might help us explain why some people go beyond boundaries which the rest of us never go near. And she could face up to her crimes instead of whining about the injustices she perceives perpetrated against her.

Hindley believes God has forgiven her. She has forgiven herself. But for now, perhaps forever, she remains unforgiven.