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McNabb-Mallory Rule

A federal judicial doctrine that operates to exclude from evidence a confession that is obtained from a person who was not brought before a judicial officer promptly after the person's arrest.

The McNabb-Mallory rule, which is applicable only in federal prosecutions, derives from the U.S. Supreme Court cases of McNabb v. United States, 318 U.S. 332, 63 S. Ct. 608, 87 L. Ed. 819 (1943), and Mallory v. United States, 354 U.S. 449, 77 S. Ct. 1356, 1 L. Ed. 2d 1479 (1957). The McNabb-Mallory rule is not a constitutional rule but is based on federal law and on the federal judiciary's authority to oversee the administration of criminal justice within the federal courts. The purpose of the rule is to provide protection against an arresting officer's "secret interrogation" of a suspect prior to the suspect's appearance before a judicial officer. Before McNabb, authorities could effectively and without penalty delay a suspect's presentment before a judicial officer in order to obtain a confession. McNabb held that the penalty for obtaining confessions as a result of such a delay is the exclusion of the confession at trial.

In McNabb, a federal revenue agent was killed when agents attempted to arrest members of the McNabb family, a clan of Tennessee mountaineers. The agents subsequently arrested three of the McNabbs and placed them in a detention cell for more than fourteen hours. Over the course of the next two days, federal agents interrogated the McNabbs and finally obtained confessions from them. Based primarily on these confessions, which were admitted into evidence at trial, a jury convicted the McNabbs of second-degree murder. On appeal, however, the U.S. Supreme Court held that the McNabbs' confessions should have been excluded from trial because the federal agents had improperly obtained the confessions by delaying their appearance before a judicial officer. A federal law at the time required federal law officers to take a person charged with any crime before the nearest U.S. commissioner or judicial officer. Relying on this law and on the Court's supervisory authority to oversee justice in the federal court system, the Court held that the confessions should have been excluded from evidence at trial. The Court noted in its decision that the arresting officers had "subjected the accused to the pressures of a procedure which is wholly incompatible with the vital but very restricted duties of the investigating and arresting officers of the Government and which tends to undermine the integrity of the criminal proceeding."

Federal courts questioned whether the McNabb EXCLUSIONARY RULE applied only in determining whether a confession was voluntary or whether it applied only when the presentation of the arrested person before a federal magistrate was unnecessarily delayed. Subsequently, the Supreme Court in Upshaw v. United States, 335 U.S. 410, 69 S. Ct. 170, 93 L. Ed. 100 (1948), clarified that a confession was "inadmissible if made during the illegal detention due to failure promptly to carry a prisoner before a committing magistrate."

The McNabb case preceded the adoption of the Federal Rules of Criminal Procedure in 1944. Rule 5(a) provided that an arresting officer must bring an arrested person "without unnecessary delay" before the nearest available federal magistrate. In Mallory, the Court held that the McNabb ruling concerning exclusion of improperly obtained confessions applied equally to rule 5(a). Justice FELIX FRANKFURTER, writing for the Court, stated:

The scheme for initiating a federal prosecution is plainly defined. The police may not arrest upon mere suspicion but only on "probable cause." The next step in the proceeding is to arraign the arrested person before a judicial officer as quickly as possible so that he may be advised of his rights and so that the issue of PROBABLE CAUSE may be promptly determined. The arrested person may, of course, be "booked"by the police. But he is not to be taken to police headquarters in order to carry out a process of inquiry that lends itself, even if not so designed, to eliciting damaging statements to support the arrest and ultimately his guilt.

Because the defendant in Mallory had been interrogated for more than seven hours, during which time a judicial officer was readily available for ARRAIGNMENT, the Court held that the defendant's confession should have been excluded from evidence at trial.

The McNabb-Mallory rule is not mandated by the Constitution. As a result, Congress frequently attempted to repeal the McNabb-Mallory rule by legislative act. Finally, in 1968, Congress passed the Omnibus Crime Control and Safe Streets Act (42 U.S.C.A. § 3701 et seq.), which allowed the admission of a confession at trial as long as the confession was "voluntary." The act made the delay in an arrested person's appearance before a judicial officer one of several factors for the courts to consider in determining whether the person's confession was voluntary and therefore admissible. Nevertheless, Supreme Court cases since McNabb and Mallory have mandated the McNabb-Mallory rule in certain cases, such as requiring that a person be brought before a federal magistrate promptly after arrest in a case of an arrest without a warrant. The McNabb-Mallory rule stands for the proposition that the federal judiciary may supervise the administration of justice in the federal courts and, in the exercise of that function, exclude evidence obtained in violation of federal law.

Although the McNabb-Mallory rule is not applicable to prosecutions of individuals in state court proceedings, some states have a similar rule. Other states exclude confessions of a defendant only if the confession was involuntarily made during the period of pre-arraignment detention.


LaFave, Wayne R., and Jerold H. Israel. 1984. Criminal Procedure. Vol. 1. St. Paul, Minn.: West.

Rhodes, Mark S. 1985. Orfield's Criminal Procedure under the Federal Rules. 2d ed. Rochester, N.Y.: Lawyer's Cooperative.


Criminal Law; Criminal Procedure.

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