These days Constance Briscoe sleeps soundly in her bed. With a sturdy iron frame, it measures more than 7ft across. “I love it. It’s so wide I can roll over in it 3½ times,” she says. After a day in court, where she presides as a judge, she falls asleep the moment her head hits the pillow. But if she hears the slightest noise, particularly on the stairs, “I’m wide awake in an instant”.

Sleep did not always come so easily. For much of her south London childhood she lay awake listening for the creak of the stair that would herald the arrival of her mother. It was only the third step that creaked, part of the tread having been removed to fashion a sharp stick. To beat her with.

“She hit me when I wet the bed,” she says. “And sometimes when I didn’t.”

Now 48, Briscoe speaks in measured, almost flat, tones recalling her troubled childhood. As she rehearses the violence, starvation and deprivation she endured, she could be reciting a shopping list.

Ugly, her account of her upbringing, makes for harrowing reading. Her Jamaican mother’s vocabulary included “Black Bitch”, “Scarface” and “Miss Pissabed”. When she asked her mother why she treated her so badly, she replied: “Oh, just the fact that you breathe . . .”

Briscoe was sexually abused by her stepfather on one occasion, but the constant cruelty came from her mother, who not only beat and kicked her, but spat at her and deprived her of food. She would punch her adolescent bosom and pull her nipples to punish her. She inflicted such damage that doctors at first believed lumps in her breasts, discovered when she was 12, were the result of cancer, not cruelty.

Her mother’s behaviour is a cancer that lives on to this day. In 1999 she tried to sabotage Briscoe’s career, writing to the Bar Council to allege that her daughter had hired a hitman to kill her. The council dismissed the claim as unsubstantiated. Briscoe’s response was to write the following to her mother: “You are a very sad and sick woman. My one regret is that you and I happened to be in the same room when I was born . . .” As a Catholic, she added, she knew that only the good die young. But “every day I pray the good Lord takes you sooner rather than later”.

Now a successful barrister who works as a part-time judge in the crown and county courts, Miss Recorder Briscoe often comes up against instances of child abuse. “I try to deal with such cases in an entirely professional way. I do not let my experiences colour my judgment.”

She has written the book to let her children, now teenagers, know “something about their mum”, and at the behest of her partner, Tony Arlidge, a writer and QC. Her daughter, studying at St Paul’s girls’ school, read it and was appalled. Her son, currently applying to Cambridge, is stuck in the middle of the story, too pained to continue.

The child of Jamaican parents who settled in Britain in the 1950s, she does not, however, see herself as a spokeswoman for the black middle class or immigrants. “I do not think what happened to me has anything to do with my race or colour.”

One of six children, only Constance was singled out for abuse. Her father walked out shortly after she was born and she was brought up by her mother and stepfather.

“My mother’s behaviour was a combination of temperament and circumstances. But now that I am a mother, I think even more that her treatment was completely incomprehensible and unacceptable. I do not forgive her.”

Ugly certainly makes for uncomfortable reading. But what makes it all doubly distressing is not just the brutality of the mother but the apparent culpability of her older sisters. Although they stopped short of relishing her humiliation, they did not intervene. “They were frightened. Pauline, the eldest, should have done more. She says when she tried to step in, she was beaten. When that happens, you give up. They were always diving for cover.”