This chapter considers whether the relevant legislation in England and Wales and in Northern Ireland complies with the United Kingdom's obligations under Article 12 of UN Convention on the Rights of Persons with Disabilities (CRPD). The European Court of Human Rights judgment in HL v the United Kingdom found that English law governing deprivation of liberty of persons considered to lack mental capacity was in breach of Article 5 of the European Convention on Human Rights. This approach diverges from the approaches adopted in England and Wales and Scotland and its compliance with Article 12 of the CRPD will be considered. Like the corresponding legislation in England and Wales, the Northern Ireland legislation provides for a presumption of capacity in respect of adults. The requirements of the CRPD and the jurisprudence of the CRPD Committee in interpreting Article 12 and allied rights provides a benchmark against which the legislation in England and Wales and Northern Ireland can be measured.