Specialised mental health legislation typically provides for the hospitalisation and treatment of those with mental disorders in the absence of their consent. The article examines the possible justifications for the existence of these special powers and argues that two of the most common justifications, the protection of the patient and the protection of others, do discriminate against those with a mental, as opposed to a physical, disorder. The relationship between mental health and mental capacity, or guardianship, legislation is then considered and possible ways forward are discussed with particular reference to the current reform debate in England and Wales.