She is planning to introduce dramatic new evidence in an attempt to prove that she took part in the Moors Murders because Brady sadistically abused her and threatened to kill her mother, grandmother and young sister.
In letters and a series of interviews with The Independent, Hindley says she will tell the court for the first time that Brady strangled, bit, whipped, drugged and blackmailed her into submission. She says the new evidence includes photographs taken by Brady showing her naked with bruises and injuries caused by bites, whips and canes.
However, her tactics are expected provoke a violent backlash from Brady, 60, now a patient at Ashworth Special Hospital in Merseyside, her victims' families, and some sections of the media. She believes Brady will publish a number of letters she wrote to him in secret code while they were awaiting trial and after their imprisonment in 1966.
In letters, a statement and conversations with The Independent, Hindley tells how the coded messages worked and why she has feared Brady releasing them for more than 30 years.
Brady's alleged treatment of Hindley, 56, will form one of two grounds in an appeal against a decision by the Home Secretary, Jack Straw, that in her case life imprisonment should mean life. The other ground, to be aired in October, will relate to her own progress as an individual and repeated claims by professionals that she is not likely to re-offend.
She was recently moved to Highpoint category C prison in Suffolk, where supporters say she has made "remarkable" progress. She suffers from angina and osteoporosis. During her time in jail, she has gained a degree in humanities and has been the subject of repeated positive assessments by psychologists and psychiatrists. Whether her latest move will be seen as a cynical attempt to lessen her culpability, or as valid mitigation, remains to be seen. Hindley and Brady were jailed for life at Chester Assizes on 6 May 1966 for the murders of Lesley Ann Downey, 10, in 1964 and Edward Evans, 17, in 1965. Brady was also convicted of murdering 12-year-old John Kilbride, with Hindley an accessory after the fact. Twenty one years later, they confessed to killing Pauline Reade, 16, and Keith Bennett, 12.
During the 15-day hearing, the jury was played a tape recording on which Lesley Ann can be heard crying: "Please mum, please God ... What are you going to do with me?"
Hindley says she wants to explain how she became involved. "I just want people to know what happened. People think that I am the arch-villain in this, the instigator, the perpetrator. I just want people to know what was going on. [Her claims] together with these pictures, will help people understand how I got involved and why I stayed involved.
"Brady will not be pleased at what I am saying, a) because he knows it is true, and b) he will not want people to think worse of him than they already do. The police found pictures of me among his possessions, when he was arrested, showing me with whip and cane marks and bruises."
She said she believes the photographs still exist and her legal team - solicitor Jim Nichol and barrister Edward Fitzgerald QC - have requested copies. Mr Nichol refused to comment yesterday; Mr Fitzgerald was not available.
Hindley added: "Brady has been threatening me for years with extracts from letters we wrote to each other while on remand. But I won't be threatened any more. He can do what he likes. I know I will come in for criticism but I won't sit on the truth because of his threats."
The secret messages do not reflect well on her. In one, she suggested Brady should get someone to throw acid on Brett, the four-year-old son of Ann West, whose daughter, Lesley Ann Downey, was killed by Brady and Hindley. She claims Brady asked her to send such messages for "stimulation".
Asked why she had never before made the claims about his treatment of her, she said: "I suffered dreadful abuse at Brady's hands but I didn't say anything about it for a long time. I felt so guilty and, frankly, I felt I deserved what I got."
The discovery that the photographs still exist is thought to have helped her reach her decision. Only three years ago, in a letter to a newspaper, she said: "I am not seeking to blame Ian Brady for what I am personally responsible for, or even to apportion blame.
"And whatever mitigating factors there were, my own conscience and acute awareness of my own culpability tell me the unpalatable truth that - excepting God's mercy - I have no excuses or explanations to absolve me for my behaviour after the first offence."
Hindley has written a seven-page statement detailing explicitly for the first time Brady's treatment of her. It alleges:
t Brady drugged her grandmother to show he could commit the "perfect murder". He also drugged Hindley and took pornographic photos with which he threatened to blackmail her.
t Brady regularly beat her with a cane, raped her, bit her, urinated on her and strangled her. Once, after she had applied for a job that would have taken her to Germany, he drugged her and "warned me that if I ever tried to get away again, I'd be the sorriest person alive".
She added: "After the first murder, as we were driving home, he told me that if I'd shown any signs of backing out, I would have finished up in the same grave as Pauline ... I just said, `I know'."
t Brady threatened her with a rifle and a knife, beating her with a broom handle and strangling her to unconsciousness after finding her crying over a newspaper advertisement that read: "Pauline, please come home. We're heartbroken for you." It related to Pauline Reade, their first victim.
Hindley added: "I used to ask him why he kept strangling me so much, so many times - this was before the offences took place - and he told me he was `practising' on me. I said one of these days he was going to go too far and would kill me, but he just laughed and said he wouldn't - he needed me. That wasn't an affectionate remark; I knew what he needed me for."
Asked what she planned to do if ever she were released, Hindley said: "I have contingency plans, but I am under no illusion that that is when another sentence begins ...
"I would like, ideally for the Home Office to let me go abroad but that would have to be negotiated. I know I could be out one week before someone assassinated me. But at least I would have had a week of freedom. I will take my chances. I would prefer one week of freedom to the security of a lifetime of incarceration."Reuse content