Rethinking necessity and best interests in New Zealand mental capacity law

This article considers the hard-earned lessons that New Zealand might draw from developments in English mental capacity law that should inform a comprehensive review of New Zealand’s equivalent adult guardianship legislation, the Protection of Personal and Property Rights Act 1988. The United Nations Convention on the Rights of Persons with Disabilities, and the shift towards supported decision-making, requires State parties to rethink domestic laws and engage with the key concepts of this important human rights convention. The most significant development under the Mental Capacity Act (England and Wales) 2005 is the identification of the so-called ‘Bournewood gap’ and the realization that the common law doctrine of necessity provides inadequate procedural safeguards for people with impaired capacity who are unable to consent or object to their healthcare and living arrangements. In addition, the ‘best interests’ standard for decision-making in English law has evolved with a greater emphasis on support for the exercise of a person’s legal capacity into this standard. This article argues that these developments should influence reform of New Zealand’s mental capacity law