In Royal Borough of Greenwich v CDM  EWCOP32, the court had to decide whether the assessment of capacity to make decisions about diabetic management is one macro-decision which encompasses all of the many micro-decisions that CDM is required to make when managing diabetes. Or, whether CDM’s capacity should be assessed in respect of each micro-decision or group of micro-decisions.
CDM’s case went to the Court of Appeal at the end of 2018 on the question of fluctuating capacity. After fresh medical evidence was introduced, it was decided that the matter should be dealt with by a first instance judge, Newton J. With the benefit of additional expert evidence, the initial decision that CDM’s capacity to manage her diabetes fluctuated as a result of her personality disorder was more fully considered.
CDM was a 64 year old woman with a range of diagnosed personality disorders and physical health problems who was deprived of her liberty against her wishes in a care home. She was found by the court to have capacity to decide where to live and to make various other decisions, but to have fluctuating capacity with regard to the management of her diabetes.
Newton J summarised the issues before him as follows:
- Whether the assessment of capacity to make decisions about diabetic management or “the matter” in relation to which CDM was being assessed was one macro-decision which encompasses all of the many micro-decisions that CDM was required to make when managing her diabetes, or, whether CDM’s capacity should be assessed in respect of each micro-decision or group of micro-decisions.
- In the light of that determination whether the presumption that CDM had capacity about her diabetes had been rebutted, and if so on what basis.
- If the conclusion that as a matter of fact CDM’s capacity to make decisions about any aspect of her diabetes management fluctuates, what preparations the court could and should make to reflect that finding.
The two experts instructed, one a psychiatrist and one a psychologist, agreed that the management of CDM’s diabetes had to be viewed at a macro-level, or as a group of micro-decisions. Their reasoning was that that the decisions had to be consistent and coherent with each other over time, and because decisions at one time would be affected by decisions taken earlier. CDM’s emotional dysregulation as a result of her personality disorders was frequent, and affected her ability to retain and to weigh information. As well as this, CDM did not understand that she was at risk of death when her insulin levels were very poorly controlled.
The Official Solicitor (on behalf of CDM) argued that the diabetes management decisions should not be treated as one decision, as otherwise CDM would have her capacitous micro-decisions overridden. Newton J rejected this analysis saying that the ‘assessment of capacity to make decisions about diabetes management… is a global decision… that CDM lacks capacity to make those decisions, and having regard to the enduring nature of her personality disorder which is lifelong and therefore unlikely to change’.
Newton J did acknowledge, along with the experts, that there were occasions when CDM had the capacity to make micro-decisions in respect of her diabetes and occasions when she did not. However, he concluded that diabetes management was a macro-decision and CDM lacked capacity to make the macro-decision to include all its health consequences. Newton J confirmed that ‘the issue of fluctuating capacity simply does not arise’. Accordingly, all actions in relation to the management of CDM’s diabetes were to be determined in accordance with her best interests.
Of note is that Newton J confirmed the decision was highly fact-specific and unlikely to be capable of easy application to other scenarios.