May the state fence in the harmless mentally ill solely to save its citizens from exposure to those whose ways are different? One might as well ask if the state, to avoid public unease, could incarcerate all who are physically unattractive or socially eccentric. Mere public intolerance or animosity cannot constitutionally justify the deprivation of a person's physical liberty.
¶ Unanimous opinion, O'Connor v. Donaldson, 422 U.S. 563 (1975)
Full opinion.
