HIV transmission and the criminal law

Since 2001, 24 people have been prosecuted in the United Kingdom (20 in England and Wales, and four in Scotland, which has a different legal system) for giving their sexual partners HIV. However, many more cases have been investigated by the police and some of these investigations may be inappropriate. This highlights the importance of good legal advice at the earliest possible stage of an investigation.

The laws used to prosecute criminal HIV transmission developed from existing assault laws – recklessly or intentionally inflicting grievous bodily harm in England and Wales and reckless endangerment and reckless or intentional injury in Scotland. The law in Northern Ireland is similar to that in England and Wales but there have been no prosecutions so far. 

If the accused has pleaded not guilty, in order to secure a guilty verdict for either recklessly inflicting grievous bodily harm or reckless injury the prosecution would have to prove during a trial that:

  • the person with HIV did, in fact, infect their partner
  • the person with HIV was aware of their HIV status and knew that there was a realistic risk of transmission
  • the person who became infected did not explicitly consent to sex with an individual they knew had HIV.

To secure a guilty verdict for intentionally inflicting grievous bodily harm or injury, the prosecution would also need to prove that the person with HIV deliberately planned to pass HIV on and succeeded in doing so. It is also possible to be prosecuted for attempting to intentionally transmit HIV. However, proving that someone planned to intentionally give another person HIV is extremely difficult. Allegations of this kind are extremely rare and there have been no prosecutions for intentional (or attempted intentional) transmission so far.

Since 2008, prosecutors in England and Wales have had guidelines which help to clarify what actions are most likely to be prosecuted, and under what circumstances. NAT and THT have produced a pamphlet explaining these guidelines to people living with HIV. 

Similar guidelines were produced by prosecutors in Scotland in 2012. HIV Scotland, NAT and THT have produced a pamphlet explaining these guidelines to people living with HIV.

There are also guidelines for the police in England, Wales and Northern Ireland to help them understand how to approach an investigation in a way that is sensitive to both complainant and accused. NAT has produced a pamphlet explaining these guidelines to people living with HIV. 

Below are some of the most frequently asked questions and concerns about prosecutions for HIV transmission. However, this information does not replace appropriate legal advice for anyone who is being investigated or charged in such cases, or who is thinking of making a complaint. Anyone personally concerned about the possibility of prosecution should contact THT Direct on 0808 802 1221 to be put in contact with expert advice as soon as possible.

Do I have to tell my sexual partner than I am living with HIV?

There is no law that requires you tell your partner before sex (whether protected or unprotected) in any part of the UK. However, should someone be prosecuted for reckless HIV transmission in England, Wales or Northern Ireland, it is a defence to argue that your partner knew that you were living with HIV and had, therefore, consented to the risk of transmission (known as 'informed consent'). Although disclosing your HIV status to your partner is not a legal defence in Scotland, you are unlikely to be prosecuted if you have disclosed.

However, proving in court that there was 'informed consent' to the risk of HIV transmission is difficult, and it may often end up being one person’s word against another. If you are concerned about the possibility of a police investigation or prosecution, then the best way to avoid such possibilities would be to make sure that (all) your sexual partner(s) explicitly agree to have sex with you, knowing that you are HIV positive, and that this agreement is recorded in a way that could be produced as evidence (e.g. online chats or text messages).

Is having unprotected sex with someone and not telling them you are HIV-positive a crime?

In England, Wales and Northern Ireland, most cases of unprotected sex that do not result in HIV transmission are not a criminal offence. The exception would be unprotected sex with the specific intent of infecting someone, even if transmission did not occur as a result.

In Scotland, unprotected sex involving a person with HIV (whether or not transmission occurs) is potentially a criminal offence. However, the risk of being prosecuted for ‘HIV exposure’ is extremely low, and this would be very unlikely if you had told your partner you had HIV and/or you were receiving antiretroviral treatment and were told by your healthcare provider that there was a low risk of transmission.

How can it be proven that one person infected another?

A very important part of the guidance for prosecutors concerns the very real difficulties in proving that one person infected another. It will be harder to prove this if the person making the complaint has had more than one sexual partner (or any other HIV infection risk) since their last negative HIV antibody test.

A complex scientific test, known as 'phylogenetic analysis', compares blood samples from both people involved, and if the virus strains are not very similar, it is possible to say with some certainty that one person did not infect the other. 

If the samples are very similar, however, this is considered to be just one – albeit important – piece of evidence supporting the claim that one person infected the other, but it cannot be used as proof on its own. Other evidence will include the medical and sexual history (for example, from medical records or diaries) of both the person making the complaint and the person who is accused, to try and understand the timing of both people’s HIV diagnoses, and whether the person making the complaint could have been infected in another way.

How can it be proven that someone has passed on HIV recklessly?

Even if it can be shown that one person has infected another, the prosecution still needs to prove that person with HIV acted recklessly. In legal terms, ‘reckless’ means the person with HIV did not intend for their sexual partner to get HIV, but did not try to stop it happening.

Specifically, the prosecution has to prove that the accused had knowledge of their HIV-positive status; understood they were infectious; and did not use 'adequate safeguards' to try and prevent HIV from being passed on. 'Adequate safeguards' could mean using condoms consistently but it could also mean that you are on antiretroviral therapy with an undetectable viral load – as long as you have been told that this is can protect your sexual partners by your healthcare provider (who will be asked to provide evidence to the police that this discussion has been documented in your medical notes). 

There is no clear guidance about legal liability for transmission following condom breakage, but THT and NAT believe that if a condom is found to have broken during sex and HIV transmission occurs as a result, it should be an adequate defence if you tell your partner you are HIV positive after you have realised the condom broke and suggest they obtain post-exposure prophylaxis (PEP).

Can someone be prosecuted if they didn’t know they were HIV-positive?

Usually if someone has not been diagnosed, they will not be prosecuted. Most people will only know they are infected once they have been diagnosed (and this will be proved by using medical records).

In exceptional circumstances – such as where someone has refused to take an HIV antibody test despite specific advice to do so by a doctor, or they do not get a confirmatory blood test following a rapid test – this might be seen as having 'deliberately closed the mind' to having knowledge of their HIV-positive status and may mean they could still be prosecuted.

What should I do I find myself accused of criminal HIV transmission or exposure?

Don’t panic. When dealing with the police, do not give permission for medical records to be accessed or say that you are responsible for the person’s HIV infection without first getting expert legal advice.

As soon as you possibly can, find a solicitor with experience of the issue and also get support from an HIV organisation. THT (THT Direct, 0808 802 1221) can put you in touch with your local HIV organisation and can also recommend solicitors.

Further information on HIV transmission and the criminal law

This information was correct as of December 2013. For the latest advice and further detailed information, call THT Direct on 0808 802 1221. In addition, the MyHIV website from THT includes a substantial section that covers the law in all UK jurisdictions and includes specific information for people who want to complain and those who are accused, as well as those who have asked to be a witness.

Contact NAM to find out more about the scientific research and information used to produce this section.

This content was checked for accuracy at the time it was written. It may have been superseded by more recent developments. NAM recommends checking whether this is the most current information when making decisions that may affect your health.