mercy killing
Mercy killing is the intentional ending of the life of a person suffering from a severe injury or terminal illness for the purpose of relieving their pain or suffering. The term is most commonly associated with euthanasia and physician-assisted dying, though it is not a formal legal term and is often used broadly in ethical, medical, and public discourse.
Legal discussions involving mercy killing often distinguish between voluntary euthanasia, assisted suicide, and a patient’s right to refuse life-sustaining medical treatment. Voluntary euthanasia occurs when a competent patient consents to the termination of their life. Assisted suicide generally involves providing a person with the means to end their own life, while physician-assisted suicide involves such assistance by a licensed medical professional.
In the United States, the Supreme Court has recognized that competent individuals have a constitutionally protected right to refuse life-sustaining treatment. See: Cruzan v. Missouri Department of Health (1990). However, the Court has also held that there is no constitutional right to physician-assisted dying, leaving regulation of the issue to the states. See: Washington v. Glucksberg (1997). Some states permit physician-assisted dying under “death with dignity” statutes.
[Last reviewed in May of 2026 by the Wex Definitions Team]
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