The Mental Capacity Act (2005) upholds a person’s rights to autonomy, providing five core principles that drives these values in practice. It directs that Mental Capacity is decision and time specific, that all decisions should be appropriately supported, and respecting their right to make what others might call an ‘unwise decision’. Examples of a specific decision might be choice of residence, contact with a set person(s), a decision over treatment, conducting legal proceedings, managing property and finances etc.
However, there are some recognised difficulties in separating decisions at times, particularly where areas might overlap. It can also be a challenge to determine just how ‘specific’ to be. This has led to some discussion around silos within the domains of Mental Capacity, highlighting the need to ensure separate distinct categories, assessing the separate domains if there is a reasonable belief that a person might lack capacity for that area. While being reminded to ensure the salient information for the decision is tailored to the decision and not blurring onto other areas, further being careful not to set the threshold for capacity too high.
The White Leopard
In recent years there has been an emerging theme in this area, described as a ‘White Leopard’ in the courts. This so-called White Leopard poses the following challenge:
If a person has been determined to lack capacity for a specific matter (such as treatment) can they then have capacity to litigate for this same specific matter?
In the case of SJ v Cardiff & Vale University Health Board & Anor [2025] EWCOP 54 it was initially determined by professionals that the person in question had capacity to litigate, but lacked capacity for their care, residence and diabetes management, which the litigation case was purposed to address. However, the legal team supporting the person had growing doubts of their capacity, and thus raised the question before the judge.
His Honor Judge Muzaffer recognised that ‘On the face of it, it is a premise that is entirely illogical, although it is clearly one open to the court to find as a matter of law’ (paragraph 72). Judge Muzaffer goes on to reflect that;
it is extremely difficult to envisage how this could work on the ground given the particular issues being litigated… if [her] delusions mean that she is unable to retrieve relevant information from her lived experience and understand the problem at the heart of the matter, she is plainly unable to use and weigh that information in the context of providing instructions to her lawyers. In turn, this inhibits her lawyers from providing advice in a way that [she] could be expected to understand and act upon, wisely or unwisely, regardless of the high level of experience and skill at her disposal. No amount of input from her legal representatives to mitigate [her] symptoms of avolition will resolve this critical underlying problem.
SJ v Cardiff & Vale University Health Board & Anor [2025] EWCOP 54, Paragraph 81
As such, he concluded that he was not satisfied that either expert who assessed the person’s capacity had sufficiently explored how she may engage within the litigation process, including the demands this would entail. Thus, from the evidence provided, there was a substantial basis to rebut the presumption of capacity regarding the person’s capacity to litigate, finding a lack of capacity to conduct the proceedings as a direct result of their cognitive impairment.
Observations about the assessment process
Within this case, there are several areas that raise some areas of concern for us as professionals working in the field of Mental Capacity. Firstly, the judge notes issues with the thoroughness of the assessors in conducting their assessment of litigation capacity. There were also issues raised with regards to the provision of practical steps to aid capacious decision making in lines with Principle 2 (paragraph 87).
This is a key point to remember for all mental capacity assessors, as we are required to tailor to both the decision and the individual. Checking case law, context and base line information, while also ensuring a person-centred grading and adaptation of assessment, consulting as appropriate and making subsequent referrals to other professionals to assist if required.
This case has been discussed in a number of forums, for which we would encourage further reading to view from the legal stance and other professionals. These include, but are not limited to:
- Local Government Lawyer, blog February 2026
- Mental Capacity Law and Policy, blog February 2026
- Essex 26 Compendium Mental Capacity Report March 2026
Find out more
Here at Mental Capacity Ltd, we provide tailored professional Mental Capacity Assessments to a high standard, for more information, and to book an assessment, or training, please use our contact page.