Medical treatment and best interests: judicial interpretation of values, wishes and beliefs under the Mental Capacity Act 2005.

Purpose: The prominence of the best interests principle in the Mental Capacity Act 2005 represented an important transition to a more resolutely patient-centred model regarding decision-making for incapable adults ("P"). This paper aims to examine the courts' consideration of P's values, wishes and beliefs in the context of medical treatment, reflect on whether this has resulted in a wide interpretation of the best interests standard and consider how this impacts clinical decision makers. Design/methodology/approach: A particular focus will be on case law from the Court of Protection of England and Wales and the Supreme Court of the UK. Cases have been selected for discussion on the basis of the significance of their judgements for the field, the range of issues they illustrate and the extent of commentary and attention they have received in the literature. They are presented as a narrative review and are non-exhaustive. Findings: With respect to values, wishes and beliefs, the best interests standard's interpretation in the courts has been widely varied. Opposing tensions and thematic conflicts have emerged from this case law and were analysed from the perspective of the clinical decision maker. Originality/value: This review illustrates the complexity and gravity of decisions of the clinical decision makers and the courts have considered in the context of best interests determinations for incapacitated adults undergoing medical treatment. Subsequent to the first such case before the Supreme Court of the UK, emerging case law trends relating to capacity legislation are considered. [ABSTRACT FROM AUTHOR]