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22 Apr 2016

Casual sex, STIs, and the criminal law

The dramatic increase in the use of dating and hook-up apps in the last few years has put casual sex, and the risks inherent in it, under public scrutiny. Sex with people who are essentially strangers inevitably means not knowing everything, or in some cases anything at all, about the other person’s sexual history or sexual health. What many people may not realise is that if they withhold some pieces of information from a sexual partner, they could find themselves falling foul of the criminal law. Unfortunately, the criminal law in this area is not always clear-cut.

The most obvious area of controversy relating to what should be disclosed prior to sex relates to Sexually Transmitted Infections (STIs). Choosing not to disclose that you have an STI prior to sex is not by itself, regardless of the ethical considerations, a crime. However, if a person does not disclose the fact they have an STI and the other person catches it, the criminal law may be engaged.

The case of R v Dica  held that where a person, at a time when they know that they are suffering from a serious sexual disease, infects another with that disease as a result of consensual sexual activity, this can amount to an offence of inflicting Grievous Bodily Harm (contrary to s20 Offences Against the Person Act 1861). A “serious” STI has not been defined in law, and so whilst there is no doubt that this applies to infections such as HIV, whether it applies to less harmful STIs remains to be seen.

Prosecution for offences of this nature are relatively rare, and are understandably controversial. To be guilty of a s20 offence, you need to have had the mental state of “recklessness”, ie. to have foreseen a risk that the other person might contract the infection but still have taken that risk. This is not straightforward to determine, particularly in the context of HIV due to the evolving nature of the science of transmission. Consider by way of example the following questions:

– Is it reckless for someone to have unprotected sex without having been tested for HIV, when they have previously engaged in risky sexual behaviour and so might have contracted it?

– Is it reckless for an HIV positive person to have unprotected sex if they have an undetectable viral load, and full knowledge of recent scientific studies which demonstrate that no transmissions of HIV have taken place from those with undetectable viral loads?

– Is it reckless for an HIV positive person to have unprotected sex with someone they reasonably believe to be taking Pre-Exposure Prophylaxis (which has been shown to reduce risk of infection by over 90%)?

There are no definitive right or wrong answers to these questions and, as a result, no clear advice on what someone should say or do if they have a serious STI and are about to engage in sexual activity with somebody they do not know well. Individuals who are accused of inflicting GBH will need to be represented by somebody who understands the legal and scientific complexities, and who can draw these to the attention of the police, who are unlikely to be fully versed in them.

Non-disclosure also raises potential issues regarding consent to sexual activity.  Consent is defined in s74 Sexual Offences Act 2003 as: “a person consents if he agrees by choice and has the freedom and capacity to make that choice”.

The current status of the law is clear that simple non-disclosure about being infected with an STI has no bearing on the issue of consent . However, what is less clear is whether you could negate consent if you actively lie about your sexual health prior to engaging in sexual activity. The courts are gradually expanding the types of situation where they will hold that the “choice” required for consent has been removed. Examples include deception as to the use of a condom , deception as to whether the man would withdraw prior to ejaculation , and deception as to gender . The current legal position regarding whether lying about HIV status (in particular) vitiates consent is that the issue has been “left open” by the courts .

Regardless of the moral and medical issues that arise when dealing with casual sex and STIs, people need to know what they are required to tell sexual partners to avoid facing a potential police investigation. It is deeply unsatisfactory that the law regarding this increasingly relevant issue remains so up in the air.

This article is published in The Barrister.

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