knowingly exposes to the public

Petitioners were convicted of armed robbery in the Circuit Court of Kankakee County, Illinois, after a trial in which the prosecution introduced a sawed-off rifle and rifle shells seized by police from an automobile in which the petitioners had been passengers. Neither petitioner owned the automobile, and neither asserted ownership of the rifle or the shells. The Illinois Appellate Court affirmed the convictions after upholding the denial of a motion to suppress, and the Illinois Supreme Court denied leave to appeal. The events began when a police officer on routine patrol received a radio call reporting a robbery of a clothing store in Bourbonnais, Illinois, and describing the getaway car. The officer spotted a vehicle he believed matched the description, followed it until backup arrived, and then stopped the car. The occupants, consisting of the petitioners and two female companions with the owner driving, were ordered out of the vehicle. After the occupants exited, officers searched the interior of the car and discovered a box of rifle shells inside the locked glove compartment along with a sawed-off rifle beneath the front passenger seat. The officers then took the petitioners to the station and placed them under arrest. Before trial the petitioners moved to suppress the rifle and shells, conceding they did not own the automobile and were merely passengers while also declining to claim ownership of the seized items. The prosecutor challenged the petitioners' standing to object to the search on the ground that neither the car nor the evidence belonged to them. The trial court agreed and denied the motion to suppress without reaching the question of probable cause. The Supreme Court of the United States granted certiorari to address the standing issue because of its importance to the administration of criminal justice.

In January 1964, fourteen-year-old Pamela Mason disappeared from her home in Manchester, New Hampshire, during a heavy snowstorm after receiving a telephone call about a babysitting job. Her body was discovered eight days later beside a major highway, prompting a massive police investigation. On January 28, officers visited Edward Coolidge at his home after learning he had been absent on the night of the disappearance. Coolidge produced three guns for inspection and agreed to take a lie-detector test. On February 2, while Coolidge was at the police station undergoing the test, two plainclothes officers arrived at his house and spoke with his wife. Mrs. Coolidge provided four guns belonging to her husband and some clothing she believed he might have worn on the night in question. Coolidge was held overnight on an unrelated charge but released the next day. Over the following two and a half weeks, the State accumulated evidence implicating Coolidge. On February 19, the results of the investigation were presented at a meeting between the police officers working on the case and the State Attorney General, who had personally taken charge of all police activities relating to the murder, and was later to serve as chief prosecutor at the trial. Coolidge was arrested at his home that day. His 1951 Pontiac automobile parked in the driveway was seized and towed to the police station two and a half hours later. The Pontiac was searched and vacuumed on February 21, again in January 1965, and a third time in April 1965. At Coolidge's subsequent jury trial for murder, vacuum sweepings from the car were introduced into evidence. One of the guns taken from the home was also introduced. Vacuum sweepings from the clothing were introduced into evidence. The New Hampshire Supreme Court affirmed the conviction after upholding the admissibility of the evidence, and the United States Supreme Court granted certiorari.

A special grand jury was convened in the Northern District of Illinois in February 1971 to investigate possible violations of federal criminal statutes relating to gambling. In the course of its investigation, the grand jury received in evidence voice recordings that had been obtained pursuant to court orders. The grand jury subpoenaed approximately 20 persons, including the respondent Dionisio, seeking to obtain from them voice exemplars for comparison with the recorded conversations that had been received in evidence. Each witness was advised that he was a potential defendant in a criminal prosecution. Each was asked to examine a transcript of an intercepted conversation, and to go to a nearby office of the United States Attorney to read the transcript into a recording device. The witnesses were advised that they would be allowed to have their attorneys present when they read the transcripts. Dionisio and other witnesses refused to furnish the voice exemplars. The Government then filed separate petitions in the United States District Court to compel Dionisio and the other witnesses to furnish the voice exemplars to the grand jury. The petitions stated that the exemplars were essential and necessary to the grand jury investigation. They would be used solely as a standard of comparison to determine whether the witness was the person whose voice was intercepted. Following a hearing, the District Judge ordered them to comply with the grand jury's request. When Dionisio persisted in his refusal to respond to the grand jury's directive, the District Court adjudged him in civil contempt and ordered him committed to custody until he obeyed the court order, or until the expiration of 18 months. The Court of Appeals for the Seventh Circuit reversed. In view of a clear conflict between this decision and one in the Court of Appeals for the Second Circuit, the Supreme Court granted the Government's petition for certiorari.

On August 16, 1974, Michael Gilletti, an undercover officer with the Philadelphia Narcotics Squad, arranged a heroin buy with Patricia McCafferty, from whom he had purchased narcotics before. McCafferty told him it would cost $115 and we will go down to Mom Santana's for the dope. Gilletti notified his superiors of the impending transaction, recorded the serial numbers of $110 in marked bills, and went to meet McCafferty at a prearranged location. She got in his car and directed him to drive to 2311 North Fifth Street, which was respondent Santana's residence. McCafferty took the money and went inside the house, stopping briefly to speak to respondent Alejandro who was sitting on the front steps. She came out shortly afterwards and got into the car. Gilletti asked for the heroin; she thereupon extracted from her bra several glassine envelopes containing a brownish-white powder and gave them to him. Gilletti then stopped the car, displayed his badge, and placed McCafferty under arrest. He told her that the police were going back to 2311 North Fifth Street and that he wanted to know where the money was. She said, Mom has the money. At this point Sergeant Pruitt and other officers came up to the car. Pruitt and the others then drove approximately two blocks back to 2311 North Fifth Street. They saw Santana standing in the doorway of the house with a brown paper bag in her hand. They pulled up to within 15 feet of Santana and got out of their van, shouting police, and displaying their identification. As the officers approached, Santana retreated into the vestibule of her house. The officers followed through the open door, catching her in the vestibule. As she tried to pull away, the bag tilted and two bundles of glazed paper packets with a white powder fell to the floor. Respondent Alejandro tried to make off with the dropped envelopes but was forcibly restrained. When Santana was told to empty her pockets she produced $135, $70 of which could be identified as Gilletti's marked money. The white powder in the bag was later determined to be heroin. An indictment was filed in the United States District Court for the Eastern District of Pennsylvania charging McCafferty with distribution of heroin, in violation of 21 U.S.C. § 841, and respondents with possession of heroin with intent to distribute in violation of the same section. McCafferty pleaded guilty. Santana and Alejandro moved to suppress the heroin and money found during and after their arrests. The District Court granted respondents' motion in an oral opinion finding strong probable cause that Santana had participated in the transaction but concluding that either an arrest warrant or a search warrant was required. The court rejected any hot pursuit justification because the events did not involve a chase in and about public streets. The Court of Appeals affirmed this decision without opinion.

In 1980 Drug Enforcement Administration agents learned that respondents James Karo, Richard Horton, and William Harley had ordered fifty gallons of ether from Government informant Carl Muehlenweg. With Muehlenweg's consent, agents substituted a can containing a beeper for one in the shipment and had all ten cans painted uniformly. Karo picked up the ether on September 20, 1980. Agents used both visual surveillance and beeper signals to track the can as it moved among residences in Albuquerque including Karo's house, Horton's house, and Horton's father's house. The signal later led agents to a commercial storage facility. There agents obtained a subpoena for rental records identifying locker 143 rented by Horton. Agents confirmed the can's presence through the beeper and the odor of ether. The can was subsequently moved to a second storage facility whose locker 15 was rented by Horton and Harley under an alias. On February 6, 1981, agents observed via closed-circuit video the removal of the cans from the second locker. The cans were loaded onto Horton's pickup truck. The truck traveled public highways to a house in Taos rented by Horton, Harley, and Michael Steele. Using the beeper, agents determined that the can remained inside the Taos house even after the truck departed. On February 7, the beeper revealed that the ether can was still on the premises. Agents noticed that the windows of the house were wide open on a cold windy day. On February 8, agents obtained a warrant to search the Taos residence based in part on beeper information. The warrant was executed on February 10, 1981. Horton, Harley, Steele, and Evan Roth were arrested. Cocaine and laboratory equipment were seized. Respondents were indicted under 21 U.S.C. §§ 841(a)(1) and 846. The District Court granted their pretrial suppression motion. The Court of Appeals for the Tenth Circuit affirmed the suppression order as to most respondents. The Supreme Court granted certiorari.