LEGAL BRIEF By Special Agent Jeffrey Higginbotham, Legal Instructor, FBI Academy In May 13, 1991, the U.S. Supreme Court decided in "County of Riverside v. McLaughlin" that the U.S. Constitution requires a judicial determination of probable cause within a prompt period of time following warrantless arrests. In effect, the Court established a maximum 48-hour period, including intervening holidays and weekends, in which persons arrested without a warrant are entitled to a probable cause determination. The Court stated that a 48-hour standard recognizes the existence of some unavoidable delay following the arrest caused in transporting arrested persons, handling bookings and late-night bookings when no magistrate is readily available, and having the arresting officer present, who may otherwise be occupied with other duties. In its decision, the Court noted, "[A] jurisdiction that provides judicial determinations of probable cause within 48 hours of arrest will, as a general matter, comply with the promptness requirement." The Court cautioned, however, that a probable cause determination held within 48 hours could be found to be unreasonable if the delay was for the "purpose of gathering additional evidence to justify the arrest...motivated by ill will against the arrested individual, or delay for delay's sake." The Court also stated that if the probable cause determination is delayed beyond 48 hours, the "burden shifts to the government to demonstrate the existence of a bona fide emergency or other extraordinary circumstance." County of Riverside v. McLaughlin may require some law enforcement organizations to modify their post-warrantless arrest practices to ensure that a mechanism exists for a judicial determination of probable cause within 48 hours of a warrantless arrest. This constitutional requirement for a prompt judicial determination of probable cause only applies where the arrested person remains in custody. It is advisable for law enforcement organizations to coordinate all such judicial determinations with the appropriate prosecuting attorney.