The terms capacity and competence are often used interchangeably, but are actually distinct. This aim of this paper is to clarify the application of these terms, and to illustrate some of the practical benefits of distinguishing them.
The concepts of capacity and competence are discussed in relation to restrictions that are placed on choice and action, respectively, when these qualities are judged to be absent. The paper explores the distinction between these two concepts in relation to their legal status, assessment, and scope.
Mental capacity refers to the ability to make decisions, while competence refers to the ability to perform the actions needed to put decisions into effect. Questions of capacity are governed by legislation (in the UK: the Mental Capacity Act (MCA); the Adults with Incapacity (Scotland) Act and the Sexual Offences Act); they apply only to people who can be demonstrated to have a “mental disorder”, and trigger best‐interests decision making and other legal provisions if capacity is assessed as absent. Questions of competence involve a range of formal and informal assessment procedures, and can apply to anyone; they arise where others possess legal powers to control a person's actions.
In addition to clarifying the conceptual confusion that exists in this area, the paper also considers some areas of practice where the MCA can be invoked to promote competence, in addition to capacity.
