Police officers often must make immediate on-the-scene judgments about an arrest. In Anglo-American jurisprudence, it is an ancient given that anyone arrested for a crime without a warrant has a right to be brought before a court officer for a determination of probable cause that he committed a crime. Otherwise he cannot be held in custody.
It is easy to see why. As Justice Lewis Powell said for a unanimous Supreme Court in 1975, "pretrial confinement may imperil the suspect's job, interrupt his source of income and impair his family relationships." Justice Powell also said, "When the stakes are this high, the detached judgment of a neutral magistrate is essential if the Fourth Amendment is to furnish meaningful protection from unfounded interference with liberty." And the justice instructed lower courts that following an arrest without a warrant, a suspect must get a neutral hearing "promptly."
Most states have interpreted "promptly" in the spirit of the court's opinion. Maryland rules define it "without unnecessary delay and in no event later than 24 hours after arrest." Many states use a similar definition. All but one federal court that have come up with a time-specific definition of "promptly" in the past 15 years have used 24 hours. But last week, the Supreme Court in a 5-4 decision said 48 hours was good enough. It did so, in an opinion by Justice Sandra O'Connor, without giving any explanation for why this much delay was acceptable, except that it might cost more to provide court facilities to meet a 24-hour deadline than it does to meet a 48-hour deadline.