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Mental capacity: Different models and their controversies

  • Brian Joseph Murray

Modern legislation in the UK addressing the issue of decision-making ability uses tests of mental capacity based on the individual's ability to understand relevant information given to them. Alternative models of mental capacity do exist, but are largely considered defunct. This article reviews these alternative models and considers their importance. Far from being irrelevant to modern views on mental capacity, these models have already been incorporated into legislation such as the Mental Capacity Act 2005. A better understanding of these models can improve clinicians’ understanding of mental capacity in general. Modern controversies such as the impact of the United Nations Convention on the Rights of Persons with Disabilities (CRPD) are discussed and ways in which our understanding of mental capacity may have to change in the future are addressed.


  1. Appreciate the different ways of considering an individual's mental capacity
  2. Understand the primacy and limitations of the functional test of mental capacity
  3. Use this understanding to manage potential conflicts or disagreements when considering an individual's mental capacity

Corresponding author
Dr Brian Murray, Oxford Health NHS Foundation Trust, Whiteleaf Centre, Bierton Road, Aylesbury HP20 1EG, UK. Email:
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Declaration of Interest


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BJPsych Advances
  • ISSN: 2056-4678
  • EISSN: 2056-4686
  • URL: /core/journals/bjpsych-advances
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Mental capacity: Different models and their controversies

  • Brian Joseph Murray
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