Mental capacity and decision-making

In this chapter we start by defining terms and approaches to the assessment of mental or decision-making capacity. We outline basic principles – from the Mental Capacity Act 2005 (MCA), which covers England and Wales, as well as from Scottish legislation –where the principles are relevant to other jurisdictions. More conceptual issues, for instance to do with values and best interests, soon emerge, especially in connection with life-sustaining decisions. We discuss advance directives and lasting powers of attorneyand various tests of capacity, along with safeguards in connection with research. We then provide some conceptual analysis of the notions of ‘capacity’ and ‘competence’. We hope to have demonstrated that capacity and decision-making are complex matters because they reflect deeper issues to do with our standing as situated human beings in the world.