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Mental Capacity Act practice guidance

Part 29


Code of Practice 3.6

In emergency medical situations it is sometimes necessary to give someone treatment without following the processes of MCA.

The MCA does not remove the common law doctrine of necessity which is used in emergencies. A common law principle is a legal concept which is established by case law and is accepted as legal. The doctrine of necessity indicates that someone who lacks capacity may be restrained using reasonable force and may be given treatment to which they have not consented which is necessary and in their best interests.

Before MCA came into force the doctrine of necessity was the legal basis by which people who did not have capacity to make decisions about their medical treatment were given treatment. MCA has changed this, in establishing the system for assessing capacity and deciding people’s best interests. (Part 6: How to assess capacity) (Part 8: Best interests decisions) (Part 12: Legal protection when applying MCA)

In emergency situations it is possible to treat someone. If a clinician reasonably believes a person lacks capacity and that the proposed treatment is necessary to save their life or to prevent a significant deterioration in their condition the treatment can be given without formal documentation of the capacity assessment and best interests decision.

MCA does not give any clear indication as to how long it would be acceptable for decisions to be made under the doctrine of necessity. It is sensible to assume that as soon as someone’s capacity can be formally assessed and their best interests decided, then this is what should happen. Clinicians should follow the consent process of their health provider agency. (Part 28: Consent and implied consent)

If the proposed treatment is not clearly necessary then MCA processes should always be followed.

Remember to check if there are any Welfare Lasting Power of Attorneys or Deputies, any valid and applicable Advance Decisions and consider if an application for an Independent Mental Capacity Advocate should be made. (Part 15: Independent Mental Capacity Advocates) (Part 17: Advance Decisions and Advance Statements) (Part 19: Lasting Powers of Attorney) (Part 23: The Court of Protection)

In an emergency someone can be conveyed to hospital without their consent and without a full assessment of their capacity. The emergency services will act on a reasonable belief about someone’s capacity or act under the common law doctrine of necessities.