Sophie died being 'choked' by her partner. He said it was a 'sex thing'.

Content warning: This story deals with sexual violence.

Sophie Moss, a 33-year-old mother of two, was killed by Sam Pybus, an occasional sexual partner, using strangulation.

A married man, Pybus had drunk 24 bottles of beer over 10 hours before heading to Moss' home after his wife went to bed. He would go to her place a few times a year.

Pybus claimed he woke up in the morning with his hands hurting and Moss unresponsive next to him. He got dressed, and left the flat while he decided what to do. He did not attempt to resuscitate her or call emergency services.

He later drove to a police station to report his story.

He told police that he would apply pressure to her neck during sex, which he claimed she encouraged. Yet, he also said he could not remember anything before waking up and finding Moss unconscious.

According to anti-rough sex campaign We Can't Consent to This, he received a sentence of four years and eight months, reduced from seven, after killing Sophie in what the Court of Appeal judge called "a risky sexual practice".

The judge said there was no evidence to suggest Pybus intended to kill Moss.

This was despite her death being the result of strangulation, and despite his own wife telling police that he had strangled her without consent during sex during the early years of their relationship.

"The kind of evidence that gets used to say that 'choking' is normal, obviously obscures the inherent violence involved in (even non-fatal) strangulation," says RMIT University academic, Dr Meagan Tyler.

"If some choking is supposed to be ok, but non-consensual strangulation is not, that tends to leave 'consent' as the only marker of whether or not harm or violence occurred — a marker that is brutally useless if a victim is dead and we can't ask if it was, indeed, consensual.

"A distinction resting on consent, alone, also creates a broader cultural issue of seeing that the problem of men's sexual violence is only a problem if women don't enjoy it or consent to it — rather than it being a problem that any man should want to engage in strangulation of another person, let alone someone they are being sexually intimate with, in the first place."

Unfortunately, Sophie's story is not unique.

Strangulation in sex.

Once considered a niche sexual kink, non-fatal strangulation, colloquially known as 'choking', during sex has become increasingly normalised, despite the extreme — and mostly unknown — risks associated with the practice.

According to new research, more than half of young Australians, aged between 18 and 35, report using strangulation during sex.

The study, by researchers from Melbourne University Law School and The University of Queensland, that included 4702 young people aged from 18 to 35, found 57 per cent had been strangled during sex at least once and 51 per cent had strangled a partner at least once.

Women were more likely to have been strangled, with more than 60 per cent reporting having had a partner choke them, while 43 per cent of men reported same.

On average, young people reported they had been strangled five times, by three partners, while only six per cent reported both being strangled and strangling a partner.

Watch: The basics of sexual consent. Article continues after the video.

Choking is a colloquial term, but the practice itself is a form of strangulation, as it’s performed by squeezing or pressing on the neck. It’s also sometimes referred to as 'breath play'.

Before the term 'choking' was popularised to describe what is essentially temporary asphyxiation or cutting off blood flow to the brain during sex, discussion of the practice was more frequently found in literature on domestic and sexual violence, where is it referred to as non-fatal strangulation (NFS).

The unknown dangers of NFS.

Choking a person during sex can cause brain injury, even when the person remains conscious. The more often people are strangled, the more likely they are to experience brain injury, and the worse it's likely to be. This includes consensual choking — but most people don't know this, the study revealed.

"We are concerned that the findings suggest that many young Australians may consent to strangulation during sex without understanding that it could seriously injure them," says study co-author Professor Heather Douglas.

"It doesn’t matter if there are no apparent injuries, or whether the person consented," Professor Douglas says.

"Brain injury can also be incremental—getting a bit worse with each choking — and the person may not know they have suffered a brain injury. The effects of repeated strangling are insidious and build over time, like the effects of repeated concussions on footballers."

Frighteningly, serious injury can take place within seconds, with the study revealing the following time frames and possible consequences of consensual strangulation:

• 10 seconds to being rendered unconscious

• 17 seconds to having a fit from lack of oxygen

• 30 seconds to loss of bowel control

• 150 seconds to death

"Choking during sex is dangerous," says certified sex educator Emma Hewitt. "There are ways to mitigate how much risk there is, but there will always be risk."

Pain and bruising of the neck, coughing, difficulty swallowing, swollen lips, nausea and vomiting frequently occur, and internal and external damage is also possible, such as injuries to blood vessels, the windpipe and the thyroid gland.

Numbness, drowsiness and a loss of coordination are other risks, as well as more severe outcomes like cardiac arrest, and damage to the larynx. For pregnant women, strangulation can also lead to miscarriage, up to months after the fact.

As well as the physical risks, there are also psychological and emotional risks, says RMIT University academic, Dr Meagan Tyler.

"The fear that can be involved even if the original scenario is — on the surface level, at least — consensual. And the after effects of what it means to have someone literally controlling your ability to breathe, and even live, while aiming, perhaps even desiring, for you to be temporarily unconscious while having sex with you. The intertwining of harm, control and sex is often very troubling to confront and unpick."

Interestingly, Hewitt says many people within the kink and BDSM communities won’t engage in strangulation at all for safety reasons, "and yet it’s still made its way into what is popularity considered normal sex".

What’s contributing to the rise?

When Dr Tyler first began researching violence against women in pornography in the mid-2000s, choking was just beginning to transition from niche to mainstream content — for male consumers.

"Pornography producers, distributors and promoters would note it as a feature of interest for consumers," says Dr Tyler.

"It both eroticises the violence and makes it profitable - there is literally an industry which is largely predicated on making violence against women sexy.

"This is not simply that correlation equals causation, pornography consumers do report trying and applying things they have seen in pornography in their own, everyday sexual interactions."

Academic and Leneen Forde Chair in Child and Family Research, Professor Silke Meyer, says it's not just the nature of mainstream pornography, but young people’s access to it, that plays a major role in the prevalence of NFS in sex.

According to Professor Meyer, research shows 1 in 4 Australian young people have viewed porn before age 12. Almost half of boys have seen porn by the age of 13, and almost half of girls by the age of 15.

Alarmingly, says Professor Meyer, 95 per cent of mainstream porn now contains violence, usually directed at women. And in 93 per cent of this content, women's responses to it are portrayed as neutral or enjoying the experience.

"Even when young people don't like the idea of it, they feel pressured to agree because porn, peers and social media tells them that 'everyone does it' and if you don't, you're a bit boring and your boyfriend will find someone else who's less 'vanilla'," says Professor Meyer.

But it’s not just pornography contributing to the normalisation of NFS, it’s all over our social media and online forums too.

"It’s become a part of the lexicon of social media with memes and comments like 'choke me daddy', and the frequent jokes and comments about allowing people we find attractive to do anything to us," says Hewitt.

"This isn’t inherently bad, but it becomes a problem when we are constantly seeing or hearing about it without context or information about consent and safety."

"I think it’s important to mention that some of this rise is because people enjoy it too and so they are talking about it more with friends. But what we are also seeing from the research is that many people are doing it because they assume their partner is into it without actually having those conversations with each other."

When we consider all of that, Professor Meyer says it’s unsurprising that young men and boys think it's appropriate to engage in violence during sex, and that young women think they have to put up with it.

"Our school based sex education leaves a lot to be desired and parents are often hesitant to talk to our children about sex and porn. For example, 66 per cent of 14-17-year-old Australians say they've never had a conversation about porn with parents or carers.

"I think as parents we can do a lot better in educating our children about safe and respectful sexual relationships and the distorted portrayal of sex in pornography. Because otherwise we leave our children's sex education to pornography."

Does the rise in NSF matter?

The short answer is, yes. We know that choking is physically dangerous. But that's not all.

"Even researchers who are often very cautious about casting judgement around sexual practices are concerned about (choking)," says Dr Tyler.

"It goes beyond questions of consent because it is harmful even when consensual. There is no kind of strangulation that is safe - that needs to be our starting point."

The other aspect to consider is the gendered nature of the practice.

"What we know is that heterosexual women are usually the ones being choked while men are the ones doing the choking," says Hewitt.

"Gender violence is a global issue, and the popularity of this activity becomes hard to separate from that fact. This is why education is so important and learning to say no or stop and to listen when someone says those things to us. With any intense form of sexual play, only doing it with someone you trust can’t be overstated."

Consent.

Despite its rise in popularity — or perhaps because of it — research shows men are attempting to choke their partners without prior discussion or consent.

"Choking might be becoming normalised but the stories we are hearing and the research that is being conducted suggest that enthusiastic consent around choking is not," says Hewitt.

"Even asking for consent is not (common) and many people are experiencing non-consensual choking which is a huge problem.

"If someone has not asked for consent, we can also assume that they have not researched how to do it safely, (as) every article or video you see about how to choke someone safely starts with a very large section about consent."

Even for those who enjoy the practice, someone doing it without a prior conversation is scary, says Hewitt.

"Just because people are talking about it or joking about it doesn’t mean it’s okay to do without asking. Even if that person has said they are into choking in a past conversation, that is not consenting to do it at that moment."

The other important question is this: can you consent to something when you don’t truly understand the risk?

"There really is no 'safe strangulation'. However, many young people are unaware of the risk (short-term and long-term)," says Professor Meyer.

"So when we talk about 'consent', we really need to talk about people's understanding of the risks involved—there is no consent unless someone agreed after having been made fully aware of all the short- and long-term risks involved."

The link between NFS and domestic abuse, and the rough sex defence.

Non-fatal strangulation has been recognised as a common form of domestic violence for quite some time now, and over the past decade we've seen an increasing focus on and understanding of the risks associated with it.

"I think we had a pretty good understanding for a while that it is a high-risk behaviour in the context of DFV and a lethality indicator," says Professor Meyer.

"This is connected to the evidence around coercive control also being a predictor of fatal violence. NFS strangulation is a powerful tool of coercion, manipulation and intimidation because it sends a clear message to the victim-survivor that the perpetrator has the ability to end the victim's life if he decided to do so."

Not all NFS takes place due to threats or intimidation, however even when the practice is consensual, there are broader repercussions when violent sexual practices are normalised, particularly via mainstream pornography.

"...it shores up an existing narrative that women should have to meet the sexual demands of their male partners, and that this, in turn, can help to create a conducive context for violence against women, including experiences of intimate partner sexual violence," says Dr Tyler.

Another complication of the increased normalisation of rough sex, and choking in particular, is the use of ‘consensual rough sex’ as a defence for rape, assault, even murder.

"I think because coercion during sex is so normalised, victims comply with an abusive partner's demands.

"And when victim-survivors finally do seek help and disclose sexual coercion or violence, including NFS, the perpetrator engages in further humiliation by suggesting that she asked for it, she enjoyed it, it was consensual and just 'a bit of rough sex'.

"Which is why many victim-survivors delay or completely avoid the disclosure of their sexual victimisation experiences because they know the perpetrator is going to continue his campaign of humiliation."

According to UK based advocacy group, We Can’t Consent To This, at least 60 UK women have been killed in episodes of so-called 'consensual' sexual violence since 1972, with at least 18 women dying in the last five years.

In 45 per cent of those killings, claims of a sex game gone wrong resulted in a lesser charge, lighter sentence, an acquittal, or the death not being investigated.

A dangerous complication, according to Dr Tyler, is the number of academics and researchers who have been apologists or event proponents for pornography, and are therefore indirectly complicit in impeding our understandings of contemporary sexual violence and the harm women experience.

"A lot of this plays out in the Grace Milane case in New Zealand, where the accused — Jesse Kempson — tried to say that her death was an accident as a result of 'consensual choking' and we had Prof. Clarissa Smith, from the UK, who has done a lot of work proposing benefits of pornography for women, actually provide expert testimony for the defence."

It has since come to light that other women had complained to the police of Kempson's violence and he was ultimately found guilty of Milane's murder.

"But we should be asking how such academic researchers find themselves offering evidence to support 'rough sex' defences and, subsequently, assisting the defence of sexually violent, and even murderous, men.

"In decades past, I think there had been a lot of focus on moving away from any perceived judgement about sexual practices and this was simply extended to analyses of pornography. But these kinds of perspectives became woefully outdated in the internet age when content and consumption shifted and violence became a normal part of even mainstream pornography."

But beyond individual safety, Dr Tyler says there are larger questions we must ask about what kind of sexual culture we are cultivating that young men want to or expect to strangle women during sex.

"This should be horrifying to anyone who thinks sexual violence is problematic."

If your sexual partner does attempt to choke you without consent, Hewitt suggests stopping them immediately, by telling them to stop and manually removing their hands from your neck if you need to.

"This is not the time to worry about their feelings or be concerned about ruining the mood, they have done that by not asking for consent beforehand. Tell them not to choke you, that you don't like it and that they should have asked before doing it."

If this has raised any issues for you, or if you just feel like you need to speak to someone, please call 1800 RESPECT (1800 737 732) – the national sexual assault, domestic and family violence counselling service.

Mamamia is a charity partner of RizeUp Australia, a Queensland-based organisation that helps women and families move on after the devastation of domestic violence. If you would like to support their mission to deliver life-changing and practical support to these families when they need it most, you can donate here.

Feature image: We Can't Consent To This.