SALLY EMERY faces a stream of abuse every time she leaves her prison cell. 'Nonce. Dirty nonce,' inmates hiss at her as she passes. Glimpsed through her cell window at night they shout out across the courtyard: 'Nonce.'

In the strange prison pecking order, Sally Emery is stuck firmly at the bottom. She lives in a small unit in Holloway prison for a handful of vulnerable women 'on Rule 43' - held away from the others for their own protection.

She is there because her baby daughter was killed. Chanel, 11 months old, died at Christmas two years ago. A blow to the stomach ruptured her bowel and caused peritonitis. Doctors also found multiple injuries inflicted up to 30 days before her death.

Sally's crime was not that she killed her daughter. It was that she failed to protect her from the child's brutal father, Brian Hedman. But Sally herself was a victim of Hedman's violence. Constant mental and physical abuse left her helpless to protect either herself or her child, argued psychologists during her trial.

Nevertheless, Sally was sentenced to four years in prison. Last month, underlining its recognition of the effects of constant battering and its willingness to show mercy to the victims of such violence, the Court of Appeal reduced her sentence to 30 months.

There is no such mercy in prison. 'Nonce', more usually used to describe sex offenders in male prisons, is yelled at all the women on Rule 43 - no matter what their offence. 'It's horrible and I can't stand it. They call us 'dirty'. I lived with Brian calling me dirty all the time and still it goes on. I can't cope with it.'

Sally is 21, frail and drained, and trying to comprehend events which saw her pregnant at 18, a mother at 19 and bereaved a year later. Her mood switches from inconsolable grief to a kind of detachment, as if she were talking about someone else's life.

This is typical of women who have suffered prolonged abuse. According to Sandra Horley, a psychologist and director of Chiswick Family Rescue, Sally has displayed all the symptoms of Post- Traumatic Stress syndrome - nightmares, anxiety, depression, insomnia, and anger.

Nothing in Sally's past would have given a hint of what was to come. She was the youngest of seven children brought up in a loving family. Her parents - Dorothy, a care assistant and Frank, a retired engineer - still blame themselves for failing to spot what was happening to their daughter and granddaughter.

Sally fell in love with Brian Hedman in the summer of 1988. He had been a fellow pupil at her secondary school in Peterborough, but it was not until they had both left and Sally was working in a local toiletries factory that they started going out together.

'He was a nice person at first . . . I think a bit shy. I knew that lots of other girls liked him and it was kind of: 'God. I'm so lucky I'm the one who's got him.' '

They moved into a bedsit shortly afterwards and that is when he first hit her. 'We started having a stupid little argument. I can't remember what it was about and I said: 'You're crazy.' He looked at me in such anger and he came rushing up and slapped me with all his force across my face. It knocked me flying and I said: 'What was that for?' '

'He said: 'Don't ever call me crazy again.' He said his father used to call him crazy. He had tears in his eyes and he said: 'I'm ever so sorry, I did not mean to,' and I felt sorry for him.' '

Sally never told anyone about the incident nor about any of the violence that was to follow. She started covering up for him, hiding the bruises, pretending she had accidentally cut her head when he knocked her against a cupboard. When he insisted on sex the night she returned from hospital after giving birth - stifling her cries of pain with his hands - she did not seek medical help for her ruptured stitches.

'There was one occasion when I tried going downstairs and he was dragging me back up by my hair and I remember him kicking me on the top of the landing and I remember trying to get into the bathroom for safety.

'Thinking back now, if I was in a relationship and I was lying on the floor and someone was kicking me in the ribs, I would leave. Looking back, I think how could I have put up with that? But it's strange. You do . . . you forgive.'

To Ms Horley, a leading expert on abuse, it is not strange. Brian and Sally's relationship followed a classic pattern of domestic violence. He was jealous and possessive, gradually isolating her from her family and friends and making her dependent upon him. He undermined her and always blamed others for his actions, particularly Sally, so that in the end she felt guilty. She lost the ability to contradict him for fear of retribution. But with that went her sense of control over her life - and that of her daughter.

'The experiences of battered women can be compared with the victims of torture, who adopt similar patterns of behaviour to survive. Their behaviour can be construed as contradictory. They deny the violence, using survival techniques of blocking out their feelings,' said Ms Horley.

So when he insisted Sally take a bath in disinfectant because she was 'dirty', she did so. When he made her strip and act out imaginary sexual acts, she did so. When he kicked their dog, Sally did nothing and later, when he beat Chanel, she failed to stop him.

Sally had seen the bruises on her daughter and had seen him hit her. She coped with that in the same way as she coped with her own injuries. She tried to keep Chanel out of Brian's way and make her please him. That Christmas Brian was annoyed because the baby did not appear pleased with her presents. Sally describes how he beat the child and held her over the stairwell. 'I was frozen. I thought if I got up, he would drop her to her death.' In fact Chanel had already received the injuries which later killed her.

The couple blamed each other for Chanel's death, both to the police and at their trial at Peterborough Crown Court. They were each charged with cruelty and assault. They were not charged with murder or manslaughter because the Crown Prosecution Service had, in its opinion, no evidence pointing to which of the two caused the fatal injuries. After a three-week trial Brian was convicted and sentenced to eight years. Sally was sentenced to half that, for failing to protect Chanel from him.

At her appeal, Lord Taylor, the Lord Chief Justice, while recognising the effects of three years of verbal and physical battering, declined an invitation to free Sally immediately. He said: 'It cannot be too clearly emphasised that a mother's paramount duty is to protect her child. Failure to do so, with the result that occurred in this case, cannot be excused by other pressures there may have been on her, unless they were such as to render her incapable of action.'

But that, said Ms Horley, is exactly what had happened. 'She had been reduced to a psychological state of paralysing terror and mental confusion, which had drastically altered her normal responses and left her in a condition of profound helplessness.'

It is a condition from which she is still recovering. However, the reduction in her sentence means Sally is now eligible for parole and she hopes to be reunited with her family before Christmas.

'Looking back . . . if only I had had the courage to tell someone,' she said. 'I have to live with what happened for the rest of my life. Chanel meant everything to me. I was so proud of her.

'Sometimes I feel it might have been a good job if I had died as well. Then Brian would have had to come to both our funerals and then people may have understood what was really going on.'

(Photograph omitted)