F (mental) was an in patient in a mental hospital and had a sexual relationship with another patient. Since doctors etc thought she would be unable to cope with the effects of pregnancy, they applied for a declaration that a non-consensual sterilisation of the woman would not be held unlawful. CA granted the declaration. It held that where the purpose of the operation was to avoid the risk of her becoming pregnant rather than the treatment of diseased organs, the fundamental and irreversible nature of the operation was such that as a matter of good practice it was highly desirable that such a declaration should be sought by those caring for the woman.
Lord Bridge: “Prima facie, therefore, in the absence of consent all, or almost all, medical treatment and all surgical treatment of an adult is unlawful, however beneficial such treatment might be. This is incontestable.” The court also has no power to consent on a person’s behalf. However the right not to be interfered with physically by others is not absolute. It must coexist with, for example, the right to treatment. Exceptions include emergency medical treatment (where consent is unobtainable), vicissitudes of life (e.g. jostling in the street). The law should also add an exception for patients who are unable to consent. This is a separate exception to emergency treatments (since here, unlike there, the doctors have time to weigh up what is the best course of action). In this category of exception, more is required to be proved than in emergency cases. The doctors must ask: "What course of action is best calculated to promote my true welfare and interests?" What constitutes true welfare and interest often gives rise to very difficult questions, but that does not affect the validity of the test.”