Video footage helped convict Tristan Carlyle-Watson and two other men of raping a teenage girl, but it is rare to have such conclusive evidence in sexual assault cases. Credit:Facebook Most sexual assaults occur under circumstances in which the justice system isn't capable of delivering a guilty verdict, because the law and the nature of the events combine to create reasonable doubt. So what do we do? Just accept that most women who have been raped will have no legal recourse against their rapists? Clearly, this is not a tolerable option, but it appears to be the only one currently available, which partly explains why sexual assaults remain so underreported. Just under 11,000 reports of sexual violence involving adults and children were made to NSW police in 2015. That same year 1603 cases of sexual violence went to court, 932 of the accused were found guilty and 523 received a custodial sentence.

Given these numbers have remained stable for the last few years, it's reasonable to assume they're a fair representation of the conviction rate for sexual violence, which works out to about 9 per cent of reported cases. When you factor in that, at most, 15 per cent of sexual assaults are reported to police, there were probably more than 70,000 sexual assaults in NSW in 2015 and about 1 per cent of them reached conviction. Despite persistent belief that women commonly lie about rape, only about 2 per cent of reported rapes are determined by police to be false. Put all those figures together and it's 283 times more likely that a rape will not be reported than that a victim is lying about rape. And why don't women report rape? The reasons are a complex interaction of vicious myths about women's responsibility for the violence enacted against them. Victims may self-blame, but they are also aware that the likelihood of getting a positive result from making a police report and – if it even makes it to court – going to trial, is impossibly low. And therein lies the conflict between fundamental principles of our justice system. The presumption of innocence and a requirement that guilt must be proven beyond reasonable doubt is necessary in a functional democracy. No one wants to live in a society where people can be incarcerated on a whim.

But justice also requires that recourse to the law is available to all victims of crime. Rape is a traumatic and horrifyingly common occurrence. It is also a crime that rarely leaves forensic evidence because the basic element of the crime is a state of mind. Conviction for rape in NSW requires proof that intercourse occurred, that it was not consensual and that the accused rapist knew it was not consensual, or had no reasonable grounds for believing it was consensual. Even if you can prove the first two are true, but can't prove he understood there was no consent, he must be acquitted. How can you prove, beyond reasonable doubt, what was in someone's mind? Most rapes are committed by someone known to the victim, most of them happen in private homes, independent witnesses are almost never present, but alcohol frequently is. Rape often occurs without leaving serious physical injuries because victims will freeze or be too scared to fight back, they choose to survive a rape rather than fight and possibly not survive it. So, the trial evidence almost always comes down to the testimony of the accused rapist and the alleged victim. This is why rape myths are an enduring factor in trials. Because very few rapes fit the myth, it's an effective method of securing a not guilty verdict.

If defence lawyers can discredit the victim's character, rendering her an unreliable witness to her own trauma; they've got their reasonable doubt. Despite many efforts at law reform over the last few decades, such tactics haven't changed since the 1950s. Is she credible? Does she remember every detail accurately? Was alcohol used as a weapon to incapacitate her, and does that cloud her memory of events? Is she so traumatised that she can't recount every detail of the rape? Did she do anything, say anything, wear anything, give any possible indication that he could have interpreted as consent, even if she didn't mean it that way? These are the elements that contribute to so many acquittals, but they were not relevant to the GoPro case. It was easy to prosecute because it did not depend on the victim's memory; the video gave jurors the opportunity to watch the rape themselves. Justice Peter McClellan, chair of the Royal Commission into Institutional Responses to Child Sexual Abuse, gave a speech last week on how the justice system deals with victims of sexual abuse. Although he was speaking specifically about child victims, he said his criticisms applies to all victims of sexual violence. McClellan supported the introduction of advocates and assistance for victims in court, better preparation for cross examination, and special hearings with dedicated judges who could prevent the worst excesses of defence lawyers and ensure victims are recognised as such, not treated as hostile witnesses for the prosecution.

Feminists have long been advocating for law reform that puts the onus of understanding consent on perpetrators rather than victims. The person instigating sex must show they ensured their partner was enthusiastically willing, rather than requiring victims to prove they did not consent. Loading Until some (preferably all) of these changes occur, convictions and reporting rates for sexual violence are unlikely to change. As McClellan said: "There is little encouragement for survivors to participate in the criminal justice system if it does not have truth as its fundamental objective. Why risk potential re-traumatisation, a risk which materialises in many cases, to merely be a player in a sophisticated lawyers' game?"