William O. Douglas,
Cleveland v. United States — Opinion of the Court
“ It is not my purpose to defend the practice of polygamy or to claim that it is morally the equivalent of monogamy. But it is essential to understand what it is as well as what it is not. Only in that way can we intelligently decide whether it falls within the same genus as prostitution or debauchery.There are four fundamental forms of marriage: (1) monogamy; (2) polygamy, or one man with several wives; (3) polyandry, or one woman with several husbands; and (4) group marriage. The term 'polygamy' covers both polygyny and polyandry. ”
