(CNN) -- Physician-assisted suicide is legal in four U.S. states and in one county of a fifth state. It is an option given to individuals by state law in Oregon, Vermont, and Washington. Individuals must have a terminal illness as well as a prognosis of six months or less to live. Physicians cannot be prosecuted for prescribing medications to hasten death. Similar Montana and New Mexico court rulings are based on judicial decision and do not mention a time line. Mandated by State Law: Oregon Vermont Washington Mandated by Court Ruling: Montana New Mexico - Bernalillo County only Other Facts: The specific method in each state varies, but mainly involves a prescription from a licensed physician approved by the state in which the patient is a resident.
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Legal in Montana, Oregon, Vermont, Washington and Bernalillo County in New Mexico.
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The process of reporting applications and deaths varies by state.
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The U.S. Supreme Court ruled that state laws banning physician-assisted suicide do not violate the Constitution.
In Washington, "only a doctor of medicine or osteopathy licensed to practice medicine in @placeholder may write this prescription...participation is entirely voluntary.