In July 2005, a 13-year-old girl was asleep in her home in Queensland. A 21-year-old friend of her stepbrother was staying the night. At some point during the night, he entered the girl’s bedroom while she was asleep. He took off the covers, pulled down his pants and raped her, while she tried unsuccessfully to push him off.

After this incident, the girl started sleeping with a metal pole in her bed for protection. When the same thing happened again, she tried to grab the pole to defend herself, but couldn’t reach it, as her hands were pinned behind her. So she kneed her assailant in the gut.

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After the fourth incident of this kind, the girl told a guidance counsellor. Her assailant was placed on trial for rape. His defence was that the girl had consented to have sex with him. He also argued that, even if the girl had not consented, he mistakenly believed that she had.

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In this respect, the defendant relied upon the mistake of fact defence, which says that a person who makes an honest and reasonable mistake about the facts should only be criminally liable to the extent that they would be if the belief had been true. Reliance on this defence is a common feature of Queensland rape trials.

How could a person who climbs uninvited into a 13-year-old girl’s bed while she is sleeping reasonably and honestly believe she is consenting to sex? In particular, how could this be so when she struggles, reaches for a metal bar and knees him in the gut?

Despite these seemingly clear cut circumstances, the Queensland supreme court found that it was open to the jury to apply the defence of mistake of fact in reaching its verdicts. The end result was that the girl’s assailant was acquitted on all four counts of rape, although he was found guilty of unlawful intercourse with a minor.

Disturbing outcomes

The case described above is just one example where the mistake of fact defence has been used in Queensland to escape accountability for rapes against vulnerable complainants, including children and people with disabilities.

As well as being used to excuse the rape of a 13-year-old girl, the defence has been relied on by a defendant who brutally beat his partner with a knife, a chair and a stick for allegedly cheating on him, drawing blood and causing serious injuries, before having sex with her.

The defence is not about drunken hook ups between mutually attracted parties

It has been successfully argued in a case where the complainant was so intoxicated that she could not stop vomiting and needed help to get to bed; when she awoke it was due to pain in her vagina, as the defendant was raping her.

The defence has been utilised where the defendant asked the complainant for sex; after she explicitly and clearly refused, he had sex with her anyway, while she struggled, said no and attempted to push him off.

It has been relied on by a serial predator who arranged for his wife’s relative to travel from the Philippines to Weipa to work in his takeaway shop; as soon as she arrived, he began molesting her, despite her resistance and protests.

The defence has been used where the complainant went to bed in her home and awoke to find the defendant raping her with a vibrator. She told him to leave the house, but then awoke again later to him raping her mouth with his penis.

Is consent a “romance killer”?

Author and sexual assault survivor Bri Lee has made a submission to the Queensland government advocating a wide-ranging review of sexual violence laws. I was a co-signatory, along with several other academics and commentators.

Lee and I are also currently co-authoring a report on the mistake of fact defence. We argue that the defence should be removed for rape charges. Failing that, it should be significantly limited, as has been done elsewhere in Australia.

The Courier-Mail recently ran an article where Gold Coast defence lawyer Michael McMillan was quoted as arguing that removing the mistake of fact defence would be a “romance killer” that would “criminalise drunken seduction”. However, this argument makes no sense, for three main reasons.

First, and most importantly, there is nothing romantic about sex where one party is not consenting. If one person thinks the encounter is romantic, while the other believes she is being raped, then clearly the romance is in the first person’s mind only.

Second, McMillan’s argument could be misused to treat drunkenness as an excuse for raping someone. This is at odds with how the law treats other serious crimes. If you get drunk and beat someone up – or even just steal their wallet – it’s rarely a sound legal excuse to say that it seemed like a good idea at the time.

Imagine that a person charged with theft says, “Sorry, your honour, I was so drunk I thought he was giving me his wallet.” The excuse would be laughed out of court. However, following McMillan’s argument, it makes perfect sense for a rapist to get up in court and say, “Sorry, your honour, I was so drunk I thought she was consenting.”

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Finally, McMillan seems to think the mistake of fact defence typically arises where two people hook up after a Christmas party and a genuine miscommunication occurs. However, given the very low reporting and prosecution rates for rape, the chances of such a case reaching the courtroom are extremely small. If it did, the defendant could argue actual consent; the mistake of fact defence would not be needed.

In a comprehensive review of all the rape cases where mistake of fact was relied on before the Queensland appellate courts, Lee and I did not find a single case of that nature. What we did find in abundance is the kinds of abhorrent cases set out above.

The mistake of fact defence for rape needs to go. In reality, the defence is not about drunken hook ups between mutually attracted parties. Mainly, it is about helping men who do not care enough about their partner’s consent to find out whether she is willing – including violent, calculated and repeat sexual offenders – to evade justice for their actions.

• Jonathan Crowe is professor of law at Bond University