Hostname: page-component-7dd5485656-bt4hw Total loading time: 0 Render date: 2025-10-25T11:12:55.645Z Has data issue: false hasContentIssue false

Co-decision-making in the assisted decision-making (Capacity) Act 2015: challenges and complexities

Published online by Cambridge University Press:  21 October 2025

Shaun T. O’Keeffe*
Affiliation:
Department of Geriatric Medicine, Galway University Hospitals, Galway, Ireland
*
Corresponding author: Shaun T. O’Keeffe; Email: sokeeffeanc@gmail.com

Abstract

Co-decision-making is the middle of the three new tiers of support for those whose capacity is in question or lacking under the Assisted Decision-Making (Capacity) Act 2015. In co-decision-making, decision-making authority is shared jointly between the person and their chosen co-decision-maker. Co-decision-making is a new and challenging concept and the capacity test to be applied by healthcare professional assessors is complex. I suggest that thinking about the minimum requirements for joint decision-making and about the idea of ‘partial capacity’ are helpful in determining where co-decision-making fits on a capacity spectrum. Whatever the difficulties, co-decision-making is a core support arrangement in the new law, and there is a responsibility on all seeking to support a relevant person to work to ensure it is a viable and useful option.

Information

Type
Perspective Piece
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of College of Psychiatrists of Ireland

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Committee on the Rights of Persons with Disabilities (2014) General Comment No. 1 on Equal Recognition before the Law. CRPD/C/GC/1Google Scholar
Curley, A, Murphy, R, Plunkett, R and Kelly, BD (2019a) Categorical mental capacity for treatment decisions among psychiatry inpatients in Ireland. International Journal of Law and Psychiatry 64, 5359.10.1016/j.ijlp.2019.02.001CrossRefGoogle ScholarPubMed
Curley, A, Murphy, R, Plunkett, R and Kelly, BD (2019b) Concordance of mental capacity assessments based on legal and clinical criteria: A cross-sectional study of psychiatry inpatients. Psychiatry Research 276, 160166.10.1016/j.psychres.2019.05.015CrossRefGoogle ScholarPubMed
Donnelly, M (2019) Deciding in dementia: The possibilities and limits of supported decision-making. International Journal of Law and Psychiatry 66, 101466.10.1016/j.ijlp.2019.101466CrossRefGoogle ScholarPubMed
Kelly, BD (2017) The assisted decision-making (Capacity) act 2015: what it is and why it matters. Irish Journal of Medical Science 186, 351356.10.1007/s11845-016-1443-5CrossRefGoogle Scholar
Grisso, T and Applebaum, PS (1998) MacArthur Competence Assessment Tool for Treatment (MacCAT-T). Sarasota, FL: Professional Resource Press.10.1093/oso/9780195103724.001.0001CrossRefGoogle Scholar
Largent, EA, Clapp, J, Blumenthal-Barby, JS, Grady, C, McGuire, AL, Karlawish, J, Grill, JD, Stites, SD and Peterson, A (2022) Deciding with others: interdependent decision-making. Hastings Center Report 52, 2332.10.1002/hast.1444CrossRefGoogle ScholarPubMed
Law Commission of Ontario (2017) Legal Capacity, Decision-Making and Guardianship. Law Commission of Ontario.Google Scholar
Ordinaire, L (2017) Who decides now and to what extent: a critical reading of the assisted decision-making (Capacity) act 2015. Hibernian Law Journal 16, 91109.Google Scholar
Morrissey, FE (2010) Advance directives in mental health care: hearing the voice of the mentally ill. Medico Legal journal of Ireland 16, 1.Google Scholar
Surtees, D (2012) How goes the battle - an exploration of guardianship reform. Alberta Law Review 50, 115127.10.29173/alr270CrossRefGoogle Scholar
United Nations (2006) Convention on the rights of persons with disabilities. Treaty Series, 2515, 3. (https://www.un.org/development/desa/disabilities/convention-on-the-rights-of-persons-with-disabilities/convention-on-the-rights-of-persons-with-disabilities-2.html). Accessed 28 January 2025.Google Scholar
Westlund, AC (2009) Rethinking relational autonomy. Hypatia 24, 2649.10.1111/j.1527-2001.2009.01056.xCrossRefGoogle Scholar