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Vulnerable with capacity

Patients who lack capacity are vulnerable because others, by definition, make decisions on their behalf. If decisions are made which are contrary to the patient’s best interests, the incapacitated person may be defenceless. Whilst vulnerability in this context is understandable, are there situations where a capacitous (possessing capacity) patient is nonetheless vulnerable to adverse decision making?

This question was comprehensively answered by a court in 2012, which was considering the behaviour of DL towards his elderly parents. DL was in his fifties, and lived with his mother (90) and father (85). It was accepted that both his parents had capacity to decide whether their son should live in their house, and the degree of contact they should have with him. The local authority was concerned that DL had, over the preceding seven years, ‘punished’ his parents, behaving in an aggressive or intimidating manner towards them. He had physically assaulted and verbally threatened them, controlling their movements and their visitors. This included limiting the contact of his parents with health and social care workers. 

Furthermore, there were consistent reports that DL sought to coerce his father to transfer the ownership of the house into his name, and applied considerable pressure to have his mother, who had a physical disability, moved into a care home against her wishes.

It was clear that the protections provided by the Mental Capacity Act 2005 could not be used to assist the parents because they did not lack capacity. Could the inherent jurisdiction of the court protect the parents from their son, or did their capacity exclude them from being objectively ‘vulnerable’, thus outside that protection?

Relying on a previous landmark judgement (Re SA, [2005]), the court emphatically concluded that the parents could be protected, since the court’s authority could be applied to people with capacity who are:

  • constrained
  • subject to coercion or undue influence
  • for some other reason disabled from making a free choice or giving or expressing real or genuine consent.

Elaborating, constraint was equated to ‘some significant curtailment of the freedom to do those things which in this country free men and women are entitled to do’. With respect to coercion or undue influence, ‘where a vulnerable adult’s capacity or will to decide has been sapped and overborne by the improper influence of another’. This might entail the influence of a close and dominating relative, and where persuasion was based upon personal affection, duty, religious beliefs, social or cultural conventions or obligations. In these circumstances, only a very small amount of pressure, ‘subtle, insidious, pervasive’, may nevertheless be powerful.

The disabling circumstances alluded to were those reducing the vulnerable person’s ‘...understanding and reasoning such as the effects of deception, misinformation, physical disability, illness, tiredness, shock, fatigue, depression, pain or drugs. Doubtless there are others.’

The judge in SA acknowledged that in many cases, a number of these features could be found, preventing free choice and genuine consent, whilst capacity is preserved.

The courts in both SA and DL were determined not to offer a definition of vulnerability, since that would limit or constrict the groups of ‘vulnerable adults’ who might benefit from legal protection. Nevertheless, the description above gives a reasonably comprehensive guide as to how a vulnerable adult with capacity may present to clinical services. It would be most unfortunate if, by virtue of their technical ‘capacity’, vulnerable patients were put beyond reach of judicial protection.


Robert Wheeler
Department of clinical law, November 2019