Before 2000, anal sex was a criminal offence. However, sexual acts between two consenting adult males in private were expressly decriminalized by an Order in Council in Montserrat (and other British Caribbean territories) by the British Government pursuant to the Caribbean Territories (Criminal Law) Order, 2000 Sections 3(1) and 3(7). According to section 4 of the order, the law was passed retrospectively. There are two exceptions to the law: group sex, or sex in public, remains a criminal offence and may also lead to a charge under gross indecency and other minor sexual offence laws.
As a British overseas territory, the Montserrat is required to comply with their obligations under the international human rights instruments which have been extended to them. Specifically this includes an adherence to the European Convention on Human Rights which highlight a responsibility to ensure non-discrimination.