Thank you for your question. Depending on where a person lives, there may be laws that specifically addresses this issue. In some places, it is against the law to knowingly expose another person to HIV, without telling that person ahead of time that they are infected. These laws would apply to persons who are already aware that they have the HIV virus.
Laws can vary from country to country, from state to state, and from province to province.
To find out if there are laws that deal with this issue where you live, contact your local health department. However, there is that minority of persons with HIV who do not tell others ahead of time about their HIV status. This is one of the reasons why it is up to everyone to protect themselves against HIV, if they are uncertain about the HIV status of their partner. Many persons with HIV unknowingly expose others to the virus. Once again, let me emphasize that most people who are aware of their HIV status are responsible individuals, who take steps to protect their sex and needle-sharing partners from getting infected themselves.