Peter Stanley (defendant) and Joan Stanley never married but lived together on and off and had three children over an 18-year period. When Joan Stanley died, the state of Illinois (plaintiff) instituted a dependency proceeding. Under Illinois law, an unmarried father was presumed to be an unfit parent. Upon the state’s showing of the father’s unwed status, the children were taken from his custody and declared wards of the state. An unwed father was not entitled to a hearing on his fitness as a parent. In contrast, all married parents, divorced parents, and unwed mothers were entitled to a hearing before the state removed their children from custody. As a result of the dependency proceeding, Stanley’s children were taken from his custody and declared wards of the state. He appealed, contending that the process violated his rights to equal protection and due process. The United States Supreme Court granted certiorari.