Around 70% of non-fatal strangulation cases in the last year have been dropped due to evidential issues, exclusive data shared with Sky News shows.

It is now three years since it became a standalone offence in England and Wales, in a landmark piece of legislation designed to protect domestic abuse victims.

Data from the Institute for Addressing Strangulation (IFAS) shows that police are implementing the offence widely – but outcomes for victims are mixed.

Warning: This article contains references to domestic abuse and sexual assault

‘Sarah’ – whose name has been changed to protect her identity – vividly remembers the first time her ex-partner strangled her, one year into their relationship.

She said: “He was drunk, and he climbed on top me. He put his hands around my throat, and he pinned me down with the strength of his body.”

Terrified, she begged him repeatedly to stop, but he carried on.

“I remember I just felt really numb and scared, but it was weird, it felt like an out-of-body experience.”

Afterwards the only words he spoke to her were “look what you made me do,” she said, and then when the ordeal was over, he carried on with his day as if nothing had happened.

This was the beginning of a pattern of abuse that continued throughout the rest of their relationship, happening on at least 30 more occasions, Sarah estimated.

It became so normalised

He strangled her when she was pregnant. He strangled her whether her children were in the house or not. It always happened during sex, though Sarah was only later able to recognise that this was rape after talking to the police, because for her it had become so normalised.

And, always, he told Sarah it was her fault – that she had somehow ‘made’ him do it.

She later went on to suffer a miscarriage because of the physical abuse.

‘A form of control’

“Looking back now I can see it was a form of control he got off on, knowing that he was in control, and he liked seeing me upset,” she said. “I thought that he was going to kill me because he used to threaten it to me. It was very, very scary.”

This fear of death is common among victims of strangulation and is a recognised tool of control and intimidation.

A US study found that victims of domestic abuse were seven times more likely to be murdered by their current or former partner if there had been an incident of non-fatal strangulation beforehand.

But this form of violence often leaves no obvious external signs of injury, meaning in some cases perpetrators could only be investigated for less serious offences like common assault, which did not reflect the severity of the crime.

What are the possible effects on health?

The potential health impacts are wide-ranging, including loss of consciousness, voice changes, difficulty in swallowing and breathing, bruising, haemorrhages, headaches, depression, post-traumatic stress disorder (PTSD), miscarriage, risk of suicide, and death (including delayed death).

Symptoms can arise weeks or months after the event.

It is for these reasons that campaigners fought for the introduction of the standalone offence, which came into effect in June 2022.

‘Much work to be done’

The IFAS has been monitoring the offence since the legislation was introduced and shared its latest report findings exclusively with Sky News.

It said there is still “much work to be done” to better protect victims of strangulation.

New figures obtained by IFAS from the Home Office reveal that over 63,000 crimes of non-fatal strangulation or suffocation were recorded by police in England and Wales in the first two years under the legislation.

There were 39,360 recorded crimes in 2023/24, on average 66 offences per 100,000 people compared with 50 per 100,000 the year before, an increase of 20%.

“Survivors who work with us have recognised time and time again how important it is to be able to see strangulation as a standalone offence and have the opportunity to progress with criminal justice proceedings,” Harriet Smailes, co-author of the report, told Sky News.

The volume of crimes recorded suggests that the offence is being widely recognised and reported by police – and the number resulting in charges, at 12%, is high compared to some other offences.

However, a significant number of investigations result in no further action due to evidential difficulties. This can happen if police or prosecutors do not believe there is enough evidence to proceed, or if the victim does not support the investigation.

This was the outcome in three in five investigations overall, including one in five investigations where the victim did support police action. Outcomes were similar in both years of available data.

“In around half of cases, there are no external, physical, visible signs of injury. That’s not to say that there aren’t internal injuries that can’t be seen just with the naked eye,” said Ms Smailes, who is a research officer at IFAS.

“It might be that that visible injury isn’t present at the time of evidence capture that might develop over time, or because there’s a difference in how individuals show bruising, for example those of different skin tones. That can contribute towards there not being enough perceived evidence to be able to progress with a police case,” she said.

In some cases where a victim disengages from police proceedings, it may be that they did not feel supported and believed in the process or felt that there were “too many obstacles”.

On the other hand, not all cases where a victim did not support police action are necessarily negative. “It might be that initial needs have been met in that instance through reporting to the police, for example, initial containment of the risk of that situation, and referrals to specialist health or mental health services,” Ms Smailes explained.

Police ‘determined’ to improve

Assistant Commissioner Louisa Rolfe is the National Police Chiefs’ Council lead for domestic abuse.

She told Sky News that securing prosecutions for strangulation is a priority for tackling violence against women and girls, and a key part of national Domestic Abuse Matters training.

“For us to do well in prosecutions, we need to understand how perpetrators operate, how they use this is a sinister way of controlling their victims. And we also know that many victims are frightened to pursue prosecution,” she said.

Investigators not only have to secure detailed evidence rapidly but also present the best possible case so that prosecutors and juries understand how an abuser is operating, she said.

“That can be a challenging job, for a police service that’s under pressure, trying to deal with a myriad of priorities. I know many investigators are passionate about getting this right.”

“We know we’re up against it when it comes to securing convictions, but we’re determined to improve,” she added.

Fewer than half were convicted

Separate research by IFAS has found that in the first year under the new legislation, only around half of the number of offences charged by police were prosecuted, and less than half of those secured a conviction.

Overall, 47% of the 1,437 prosecutions of non-fatal strangulation and suffocation offences in the year to June 2023 resulted in conviction, based on data from the Ministry of Justice (MoJ) from all courts in England and Wales.

There are several potential reasons that a prosecution may be unsuccessful, including evidential difficulties or a victim withdrawing from the process.

The accused may also have been convicted of a separate offence, but not for the strangulation. Without more detailed data, it is hard to determine to what extent each is contributing to the low conviction rate.

Reflecting on the figures, head of policy and public affairs at domestic abuse support charity Refuge, Ellie Butt, told Sky News that victims often face “huge pressure” from perpetrators to drop out of the criminal justice process.

“When compounded with lengthy court delays and insufficient support, many survivors are forced to withdraw from the process. Police and prosecutors should be working to build cases that can be taken forward even when a survivor can no longer continue,” she said.

The Crown Prosecution Service highlighted to Sky News that the number of new prosecution proceedings has been consistently increasing, particularly domestic abuse-related strangulation offences.

In the latest quarter, 2,000 cases reached their first hearing at magistrates’ court.

Kate Brown, the CPS national lead for domestic abuse, said: “Three years on, we have continued to bring more charges quarter on quarter, with over 2,000 seen in court in the past three months.

“This standalone offence has shone a light on those who seek to use these violent acts to exert power over another person and harm them. We are determined to continue bringing abusers to justice for victims.”

A gendered crime

The new data from IFAS reinforces that strangulation is a gendered crime. Around 80% of victims whose gender was recorded by police were female, while 88% of suspects were male.

The data also shows that while people from all ages are impacted, most victims are younger, with three in five aged 34 or under. The age profile of suspects was slightly higher, with three in five suspects aged between 25 and 44.

‘I want to say it’s not your fault’

Sarah’s case ended in evidential difficulties.

Though her case was reported before 2022, when strangulation became a specific offence, she said she did provide substantial physical evidence to the police and she feels “let down” by the justice system.

She said she has been diagnosed with PTSD, anxiety and other health issues.

“I live with it every day. It can be a song that comes on the radio or a sign or somebody’s name and it would just bring everything back to me to that point, that moment,” she said.

“I want to say it’s not your fault. Nobody has the right to control you, nobody has the right to abuse you, rape you, strangle you.

“I would urge anyone to speak out and if you feel like you haven’t been heard and your voice has not been listened to, speak out again.”

If you or someone you know is a victim of domestic abuse, support is available.

The Data and Forensics team is a multi-skilled unit dedicated to providing transparent journalism from Sky News. We gather, analyse and visualise data to tell data-driven stories. We combine traditional reporting skills with advanced analysis of satellite images, social media and other open source information. Through multimedia storytelling, we aim to better explain the world while also showing how our journalism is done.