Article Text

Download PDFPDF
Questioning our presumptions about the presumption of capacity
  1. Isabel Marie Astrachan1,
  2. Alexander Ruck Keene2,3,
  3. Scott Y H Kim1
  1. 1 Department of Bioethics, National Institutes of Health Clinical Center, Bethesda, Maryland, USA
  2. 2 39 Essex Chambers, London, UK
  3. 3 Dickson Poon School of Law, Kings College London, UK
  1. Correspondence to Dr Scott Y H Kim, Department of Bioethics, National Institutes of Health, Bethesda, Maryland, USA;{at}


All contemporary frameworks of mental capacity stipulate that we must begin from the presumption that an adult has capacity. This presumption is crucial, as it manifests respect for autonomy and guards against prejudice and paternalism on the part of the evaluator.

Given its ubiquity, we might presume that we all understand the presumption’s meaning and application in the same way. Evidence demonstrates that this is not the case and that this has led to harm in vulnerable persons. There is thus strong reason to question our presumptions about the presumption of capacity.

We distinguish between two main ways of understanding and applying the presumption of capacity, and advocate for the one that we argue mitigates risk of harm. Our proposed interpretation offers many advantages in that it is consonant with actual practice of capacity evaluations, precludes confused and abusive avoidance of needed evaluations, and preserves the respect for autonomy motivating the presumption in the first place.

  • Capacity
  • Decision Making
  • Ethics

Data availability statement

No data are available. Not applicable.

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Data availability statement

No data are available. Not applicable.

View Full Text


  • X @scottbioethics

  • Contributors All authors contributed to the initial conceptualisation of the paper, IA wrote the first draft, all edited the entire draft for intellectual content, and all approved the final version. SK acts as guarantor.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.