Introduction

This chapter will deal with that element of clinical consent termed, most commonly, capacity. The philosophical underpinnings of the term will be considered, along with the practical implications of evaluating a person’s capacity. The law relating to capacity varies around the world, and reference will be made to differing judicial approaches and interpretations.

What, then, is capacity in a clinical context? In fact, it is difficult to separate a general view of clinical capacity from that in other areas: it is simply a person’s ability to consider something and to make a decision about it. In the domain of consent, it is held to be the ability to give consent or to refuse treatment. In other chapters, we consider issues that are substantively different: whether consent is coerced or uninformed for example. Each of these elements of consent assumes that the person of whom consent is sought is able to understand the nature and implications of the decision.