This isn’t an easy topic. Common law, the Mental Capacity Act, the Mental Health Act, judicial interpretation of both, the European Convention on Human Rights and judgments of the European Court of Human Rights are all relevant. Is the treatment for mental disorder, physical disorder or both? If it is for physical illness, is the illness related in some way to the patient’s mental disorder? Is the patient detained under the MHA and, if so, is it a section to which the consent to treatment provisions of the Act apply? Is the patient subject to a Community Treatment Order (CTO), in hospital or in the community, on section 17 leave or conditional discharge? What form of treatment are you considering? How old is your patient, are they competent and/or do they retain decision-making capacity? All of these questions need to be answered in order to decide whether or not the treatment can be given. It is important to remember that, if possible, the consent of the patient should always be sought, even if it isn’t required.