Clear and convincing evidence is required by the Fourteenth Amendment in a civil proceeding brought under state law to commit an individual involuntarily for an indefinite period to a state mental hospital. Decided April 30, 1979 (argued November 28, 1978). Opinion of the Court: Warren E. Burger → go there Applied: the Fourteenth Amendment → go there Topic: Restrictions on involuntary commitment. Addington v. Texas, 441 U.S. 418 (1979), is a landmark decision of the US Supreme Court that set the standard for involuntary commitment for treatment by raising the burden of proof required to commit persons for psychiatric treatment from the usual civil burden of proof of "preponderance of the evidence" to "clear and convincing evidence". Wiki link