Natalie Hemming was killed by her partner after she tried to leave him – just one of many deaths in which a coercive and controlling partner is a significant factor. However, despite new laws, progress in raising awareness has been slow

Margaret Hammond, 73, sits in a wheelchair, clutching her pink dressing gown. She’s white-haired and frail, but her voice is surprisingly strong – until she starts talking about her daughter, Natalie. “She was my baby,” she whispers, and briefly, silently, sobs.

On 1 May last year, 31-year-old Natalie was murdered by her former long-term partner, Paul Hemming. Despite eventually pleading guilty to manslaughter, Hemming, now 43, refused to tell police where he had dumped Natalie’s body, so her mother, siblings and three children had to endure three weeks of anguish and uncertainty before she was found. Hemming was convicted of murder.

When she has composed herself, Margaret describes her daughter’s life with Hemming, whom Natalie met when she was 20 and living in Hertfordshire. Her relationship with the father of her newborn baby daughter had collapsed – he was in the navy and lived far away – and so she was very vulnerable, her mum says.

Hemming, Margaret remembers, would “come over, all suave and sophisticated” – and Natalie fell for him. “I said, at first, ‘He’s quite nice,’’’ Margaret says. He kept promising Natalie he would marry her; she bought a dress, told her friends, made excited plans. Hemming even booked a venue – using Margaret’s money. But three times he called the wedding off. Despite their failure to wed, Natalie took his name. Four years into the relationship, she gave birth to their son, who is now seven. Three years later, they had a daughter. When their children were baptised, he refused to attend the family gathering. When Natalie got a job at a Mercedes dealership, Margaret remembers him saying: “I’ll pay you to stay at home.” Hemming also refused to allow Natalie’s eldest daughter to see her father. He would periodically throw Natalie and the kids out of the house. Over time, the control escalated. He refused to put her name on the house deeds, monitored her mail, scrutinised her bank statements and tampered with her phone.

After one attempt to leave – when Natalie fled hundreds of miles with her children to Yorkshire, where her sisters live – “he followed her and got his way back in again”, says Margaret. Eventually, in the spring of 2016, she made the psychological break. Margaret is adamant that the relationship was over some months before her disappearance. “They were sleeping in separate beds, and she hadn’t worn her engagement ring for months.”

But Hemming couldn’t accept the rejection, or that Natalie wanted her freedom. On the day he discovered she was beginning a relationship with another man, he killed her.

The police investigation into Natalie’s murder – the judge at Hemming’s trial called him “overbearing, controlling, jealous” – is now the subject of a Channel 4 film, Catching a Killer; her death is, however, just one of many hundreds of homicides in which coercion and control are a significant factor within an intimate relationship that ends in catastrophe.

A recently published study of 358 domestic homicide reviews by Dr Jane Monckton-Smith, of Gloucestershire University, showed that control was seen in 92% of domestic killings, obsession in 94%, and isolation from family and friends in 78%. These types of behaviour can lead to a victim having no life of their own, and no privacy from their abuser, who will frequently monitor them day and night. “Coercive control has similar behavioural characteristics to stalking,” Monckton-Smith observes. Coercive and controlling behaviour has been a criminal offence in this country since the Serious Crime Act 2015 came into force 18 months ago. Given the newness of the legislation it’s perhaps not surprising that campaigners say the subtlety and destructiveness of the behaviours coercive control can encompass are sometimes poorly understood by the Crown Prosecution Service, lawyers, magistrates and judges. Coercive control is not a “soft” form of abuse: Monckton-Smith says that the risk posed to victims, particularly when they attempt to separate, is well known by academic researchers. The government, she says, brought in the legislation “because coercive control is really dangerous to women and children, not just because it’s unpleasant.”

But what exactly is it? Lisa Aronson Fontes, a psychologist at the University of Massachusetts and the author of Invisible Chains: Overcoming Coercive Control in Your Intimate Relationship, observes that there is plenty of nasty behaviour that goes on in relationships that would never be viewed as abusive by a criminal or indeed a family court. Aronson Fontes describes coercive control as a situation in which “one partner is usually socially isolated [and] afraid to anger her partner [because of] the punishment that might ensue”. In ordinary bad relationships, Aronson Fontes suggests, both members of couple might shout when they are having an argument, whereas “in coercive control, the controlling behaviours suppress conflict. One member of the couple … [victims of coercive control are overwhelmingly female] is deprived of the resources she needs – such as money, friends and transportation – to have autonomy. She loses her own perspective … Over time many victims feel like they cannot ‘think straight’. People’s lives are ruined by coercive control … they often lose their jobs, their self-esteem and the freedom to make even the most minute choices in their lives. ”

Campaigner Min Grob, who has herself experienced this kind of relationship, puts it another way. “Coercive control is bespoke to the victim,” she says. “It’s not the behaviour, it’s the intention behind it.” Professionals such as police and lawyers, she says, tend to have in their minds a list of typical diagnostic behaviours, “and with some ex-partners you could tick every box, but actually they’re just arseholes – they didn’t mean you harm”.

The example Grob gives shows exactly how bespoke coercive control can be. A friend’s ex-partner put all the house bills in her name, “and she was always terrified about being overdrawn or in debt. He’d say to get home at a particular time, and if she was late or too long at the shops, he’d turn the heating on full and all the hot water taps on, and her bills would go up and the house might have flooded.”

Natalie Hemming wouldn’t have thought to call the police about behaviour that wasn’t violent, confirms her sister Jo Beverley. “He would put her down, but quite subtly. I know he threatened that if she tried to leave he’d tell social services she was a bad mum ... [but] no, I don’t think she understood she was in an abusive relationship in a way that you might go and report it.”

However, police forces are now bringing cases to court – and getting convictions. Ministry of Justice figures just out state that 155 defendants were prosecuted for coercive control in 2016, with 59 found guilty and 28 of those sent straight to prison.

At Halifax’s central police station, I meet detective constable Rachel Bourke of West Yorkshire police. She was the investigating officer who last autumn persuaded the CPS to prosecute Graham O’Shea on a “pure” charge of coercive control – without any accompanying charges for physical assault – for the extreme psychological trauma to which he had subjected his victim over the period, of just six weeks, that they were going out. It was the first conviction secured by the force – they have since had two more – and Bourke is fizzing with righteous delight that not only did a jury find O’Shea guilty in just 28 minutes, but that he was sent down for four years – longer than many sentences for actual bodily harm. “I think the judge was fantastic,” says Bourke. Before sentencing it is standard for a judge to ask for a victim-impact statement. “But he said he didn’t need one because her evidence was so compelling,” says Bourke. “She was hyperventilating, her clothes were sticking to her: I had to literally hold her hand.”

Bourke had initially been concerned the CPS would not permit O’Shea to be charged, given the brevity of the relationship, but after she detailed the manner in which he controlled her – “He wasn’t letting her wash; she smelled, she was dirty and dishevelled; he would make her have sex with him every night; he had her bank card, and he wouldn’t put any gas or electric on the meter” – Bourke says that in fact “they weren’t scared of using the legislation. Nor was the force. They were eager.”

It is now vital, Bourke says, for police and agencies to use the convictions being secured to reassure victims that if they report this type of behaviour, their claims will be investigated.

When it comes to the family courts, however, domestic abuse campaigners, barristers and solicitors are voicing concerns that coercive control is not being taken seriously enough.

Claire Waxman, the director of Voice4Victims, which campaigns against abuse of process in the justice system, is clear that some individuals deliberately abuse the justice system to continue controlling their former partner. Even if a criminal court has put a restraining order in place, perpetrators can easily and cheaply start proceedings in the civil or family courts, she says. At that point, a victim has no option but to turn up and face their former partner.

Waxman cites one such case that has gone on for four years, where a judge opted not to follow recommendations by Cafcass (which acts for children in the family courts), police and a Marac (a multi-agency conference convened to protect women at high risk of domestic abuse) all urging that a father should have no contact with his child because of the risk to the mother. The stress of the lengthy court case had reduced the woman to such a fragile mental state that social services instituted proceedings to remove her child. This sort of situation is not exceptional, say campaigners: in the high court last February, Mr Justice Moor allowed a mother’s appeal against a more junior judge’s order that there should be contact between a father and his children despite evidence of coercive control and findings against him of threats to kill.

The family and civil courts are “a brilliant route for a perpetrator,” says Waxman, “because they get to see and control their victim. I call it state-sanctioned abuse.” Voice4Victims is calling for any application to the family or civil court by individuals subject to restraining orders to be pre-vetted by a district judge, to decide whether the claim is genuine or should be thrown out.

Anyone alleging coercive control in a family court will, of course, have to prove it. And given that this particular offence is often made up of many small, sometimes seemingly trivial events or behaviours that have to be viewed together, family barrister Emily Rayner says this can be impossible to achieve when a judge – trying to cope with massive case-lists in an overstretched system – refuses to hear evidence on 20 such incidents, and instead will listen to just a handful. “If you’re pleading a course of behaviour, that’s quite hard because it’s [likely to be] a number,” she explains. “And it’s probably going to be more than six.”

At Resolution, the national organisation of family law solicitors, the chair of the domestic abuse committee, Philip Scott, says more judicial training must be a priority. “We’ve come a long way, but there is still not enough awareness,” he says. Assuming that findings of coercive control are made in a family court, Scott says resources must then be made available to protect victims and support perpetrators to change.

Coercion and control, however, do seem to be traits that perpetrators cling to. Having murdered their mother, Paul Hemming continued to try to control the children’s lives. While on remand, he held sole parental responsibility for the youngest two, and told social services he wanted his own family to care for them rather than Natalie’s sisters — thus requiring them to use legal means to fight back. They worry he will continue to petition to see them – and that they will have to engage with him again.

Margaret says she finds it hard to know how to grieve for her daughter. Guilt is ever-present. “I just think, maybe I could have done more,” she says. “But can you?” She says that if just one person recognises their situation mirrored in what happened to Natalie – and then finds the strength to get out – there will be comfort in that. “It’s never going to take the pain away,” she says bleakly, “but it’s just letting people know.”

Catching a Killer: The Search for Natalie Hemming is on Channel 4 at 9pm on Thursday 1 June.