Sister in Law by Harriet Wistrich review – in defence of women

In 2011, Harriet Wistrich got a call about Sally Challen, who had been convicted of the murder of her husband, Richard. Sally had bludgeoned him to death with a hammer at their Surrey home and driven to Beachy Head in Sussex with the aim of jumping off the cliff (she was talked down by suicide prevention negotiators). Challen’s family felt her defence team had failed to highlight Richard’s abusive behaviour towards Sally. In court she had been painted as a jealous wife, enraged by her husband’s infidelities.

At first, Wistrich, a lawyer specialising in human rights cases, struggled to see how she might help Challen, whose defence of diminished responsibility had already been rejected by a jury. Appealing against a criminal conviction without fresh evidence is no easy task. But, talking to Challen in prison, Wistrich was able to build a detailed picture of Richard’s campaign of abuse, which included gaslighting, sexual violence, isolating his wife from friends and family and withholding money. At the time, parliament was debating legislation that would recognise coercive control, an insidious form of abuse where perpetrators exert their power over victims through intimidation, humiliation and punishment. Here, Wistrich realised, was “a new framework for interpreting the dynamics of an abusive relationship. It was like placing a powerful new lens in front of existing facts and everything suddenly becoming clear”.

In Sister in Law, a series of essays detailing Wistrich’s most high-profile cases, she recalls the appeal, launched on the basis of coercive control, which led to the quashing of Challen’s murder conviction. After prosecutors accepted a manslaughter plea, she was freed from prison, having already served a nine-year sentence. It was a landmark victory that would lead to the Criminal Cases Review Commission looking at more than 3,000 murder cases to identify any unsafe convictions.

While this book is not a memoir – we learn little of Wistrich’s upbringing or interior life, which is both understandable and a bit disappointing – it nonetheless reveals its author to be courageous and terrier-like in her quest for justice. She started out not as a lawyer but an activist and film-maker. In the early 1990s, she and her partner, the writer and campaigner Julie Bindel, were enraged by what they saw as the misogyny embedded within the criminal justice system. Back then, rape within marriage had only just been made a crime, the police favoured a non-interventionist approach to cases of “battered wives”, and harassment, stalking, forced marriage and so-called honour-based violence were not recognised as offences in law.

Wistrich not only illustrates the ways in which the law fails women but the gruelling nature of litigation

It was the case of Sara Thornton, who in 1991 appealed against a life sentence for killing her violent, alcoholic husband, that prompted Wistrich’s change in career. Sara had stabbed Malcolm Thornton in the middle of a violent altercation and immediately called an ambulance. Days after Sara’s appeal was rejected, Joseph McGrail used the defence of provocation during his trial for the murder of his partner, Marion, whom he had kicked to death. He was given a two-year suspended sentence and was told by the judge that his partner “would have tested the patience of a saint”.

And so Wistrich began training as a lawyer, marking the start of a career that would see her acting for the victims of the serial rapist John Worboys; the family of Jean Charles de Menezes, shot dead on the London underground in 2005 by armed police; the victims of “spy cops”, the undercover policemen who infiltrated leftwing groups and began sexual relationships with female activists; and the female detainees at Yarl’s Wood Immigration Removal Centre in Bedfordshire, many of whom escaped torture and incarceration in their own countries only to be locked up and abused by UK immigration staff.

In reflecting on these cases, Wistrich not only illustrates the ways in which the law fails women but the gruelling nature of litigation: it is slow, infernally complicated, and forces individuals to relive their worst experiences. Yet through these enraging and astonishing stories, Wistrich also shows us the best of humanity. These are the individuals who endure punishing legal processes not just for themselves but because they want to make the system better and prevent others from going through what they did. Then there is Wistrich herself: empathetic, dogged, canny, always up for the fight. Her book might be short on introspection but her remarkable legal career speaks volumes about the person she is.

• Sister In Law: Fighting for Justice in a System Designed by Men by Harriet Wistrich is published by Torva (£22). To support the Guardian and Observer order your copy at guardianbookshop.com . Delivery charges may apply.