Mental Capacity Act: The Law of Necessity | QCS

Mental Capacity Act: The Law of Necessity

July 6, 2015

The Law of Necessity

How does a story of shipwrecked sailors from the 19th century relate to the way in which the Mental Capacity Act works? The answer lies in the common law doctrine of necessity!

In the case of Regina v. Dudley & Stephens, a group of sailors stranded at sea decided the only way they could survive was to eat the young cabin boy. As a result of killing him the other three were tried for murder, but they adopted the defence of ‘necessity’. They said they had to kill him in order to eat him because otherwise they would have perished.

The court did not accept this defence and the view was taken that they might have been found and survived anyway. However, they received only six months in prison when, otherwise, they would have expected to hang.

To treat or not to treat

How does this duty of necessity work in relation to people who lack mental capacity? Think of a scenario where you are a member of staff working with a vulnerable person who is suffering from an infection. The infection needs treatment and without it, the person’s physical and perhaps mental health will deteriorate. The person says quite clearly that they don’t want treatment, however you have come to the view – perhaps in conjunction with their doctor – that they lack the mental capacity to decide what is best for them.

So now what is your alternative? Say there is nothing can be done?
No, something must be done – it is necessary!

In addition to the necessity to act, mental capacity law tells us that however we act, it must be in the best interest of the person. So there may well be a number of other factors involved here.

What are the consequences of not treating the infection? How serious are these? If we do treat the infection, how will this be done? By using an injection?
What will the consequences of that if the person fights off any attempts to administer the injection?

I’ve written before about the idea of a balance sheet approach and how it can help in deciding what is in someone’s best interest.

Having to act

Sometimes the Mental Capacity Act can seem quite complex, but its basis is quite simple. Remember before 2005 (2003 in Scotland), we did not have any statute law to tell us how to work with someone who lacked the capacity to make decisions. We relied on the common law of necessity, and in many ways it is still a useful way of thinking. Is it necessary to make a decision on someone’s behalf? If so, is our decision in the person’s best interests?

David Beckingham – QCS Expert Mental Health Contributor


placeholder Image
May 28, 2024
Protection Against Redundancy
Read more
placeholder Image
May 21, 2024
Paternity Leave: The Changes
Read more
placeholder Image
May 21, 2024
X is for X-Ray
Read more