In English Law, an adult has the right to make decisions affecting his or her own life, whether the reasons for that choice are rational, irrational, unknown or even non-existent. This right remains even if the outcome of the decision might be detrimental to the individual (Re T (Adult: Refusal of Treatment), 1992) or to a viable foetus (Re S (Adult: Refusal of Medical Treatment), 1992). However, such a right to self-determination is meaningful only if the individual is appropriately informed, has the ability (capacity) to make the decision and is free to decide without coercion (Grisso, 1986).