The County of Riverside, California (County) (defendant) had a policy of combining probable-cause determinations with arraignments in cases of warrantless arrest. The policy required that arraignments must be conducted within two days of arrest, excluding weekends and holidays. Donald Lee McLaughlin (plaintiff) brought a class-action lawsuit against the County, challenging the policy. The district court certified a class of all present and future prisoners in the County jail, including people who had been arrested without warrants and detained since McLaughlin filed his complaint, as well as future detainees who were arrested without warrants and held without arraignment, probable-cause hearings, or bail hearings (plaintiffs). The plaintiffs sought a preliminary injunction requiring the County to provide judicial probable-cause determinations in cases of warrantless arrest within 36 hours of the arrest. The district court issued the injunction and ruled that the probable-cause determinations must be made within 36 hours of a warrantless arrest, except in exigent circumstances. The United States Court of Appeals for the Ninth Circuit affirmed the district court's order granting the preliminary injunction. The Ninth Circuit found that the County's policy of providing probable-cause determinations within 48 hours of a warrantless arrest did not comply with the rule announced in Gerstein v. Pugh, 420 U.S. 103 (1975), which required a probable-cause determination "promptly after arrest." The Ninth Circuit stated that no more than 36 hours were necessary to complete the administrative process incident to arresting someone. The United States Supreme Court granted certiorari to resolve a conflict between the circuit courts about what constituted a "prompt" probable-cause determination in accordance with Gerstein.