As a threshold matter it is clear that the mere presence of electronic equipment inside a home, transmitting information to government agents outside, does not, in and of itself, infringe on legitimate expectations of privacy of all who have an expectation of privacy in the home itself. Expectations are formed on the basis of objective appearances, not on the basis of facts known only to others. By attaching the beeper and using the container to conceal it, the Government in the most fundamental sense was asserting "dominion and control" over the property — the power to use the property for its own purposes. Respondent Rhodes was indicted only for conspiracy to possess.

The Court held that, since the movements of the automobile and the arrival of the can containing the beeper in the area of the. Justice John Paul Stevens stated that the beeper’s installation was a search and a seizure for Fourth Amendment purposes. U.S. 705, 718] In United States v. Knotts, 460 U.S. 276, 103 S.Ct. While Rawlings v. Kentucky, 448 U. S. 98 (1980), establishes that one may not have a reasonable expectation of privacy in the contents of a container in the possession of another, the search in that case did not occur in Rawlings' home, see id.

The argument that a warrant requirement would oblige the Government to obtain warrants in a large number of cases is hardly a compelling argument against the requirement. U.S., at 171

The United States appealed but did not challenge the invalidation of the initial warrant. Mounted inside a container, it has much in common with a microphone mounted on a person. U.S. 427 The homeowner who permits entry into his home of such a container effectively surrenders a segment of the privacy of his home to the privacy of the owner of the container. Footnote 7 Post at 468 U. S. 724.

The argument that a warrant requirement would oblige the Government to obtain warrants in a large number of cases is hardly a compelling argument against the requirement.

"One point on which the Court was in virtually unanimous agreement in Robbins [v. California, 453 U. S. 420 (1981)] was that a constitutional distinction between 'worthy' and 'unworthy' containers would be improper. It is compromised the moment the invasion occurs. U.S. 705, 717].

For example, United States v. White, supra, permitted the use of information obtained from within a home by means of a microphone secreted on a Government agent.

The Government contends that it would be impossible to describe the "place" to be searched, because the location of the place is precisely what is sought to be discovered through the search. The concealment of such items on personal property significantly compromises the owner's interest in privacy, by making it impossible to conceal that item's possession and location from the Government, despite the fact that the Fourth Amendment protects the privacy interest in the location of personal property not exposed to public view. 394 A government informant who sold ether containers told the Drug Enforcement Agency (DEA) (plaintiff) that James Karo (defendant) had ordered a large quantity of ether that Karo was going to use to process cocaine.

U.S. 165, 176 [2] The Court of Appeals reversed as to Rhodes since he had not shown that the beeper had been located in any place in which he had a reasonable expectation of privacy, nor had he shown any possessory interest in the ether itself that would have been invaded by the installation of the beeper. It is clear that the actual placement of the beeper into the can violated no one's Fourth Amendment rights. "Common authority . It was at that point that the infringement of this constitutionally protected interest began. power has no legitimate expectation of privacy in the movements of the container. [ Rawlings v. Kentucky, 448 U. S. 98 (1980), is simply inapposite, since it was not Rawlings' home in which the challenged search occurred.

Rawlings v. Kentucky, 448 U. S. 98 (1980); United States v. White, 401 U. S. 745 (1971); Lopez v. United States, 373 U. S. 427 (1963). Moreover, here the agents could not have employed visual surveillance to determine when the can was moved for fear of detection. Because the beeper enabled them to learn the location of personal [735] property not exposed to public view, it invaded an interest embraced in the Fourth Amendment's conception of a "search. 468 U. S. when beeper surveillance reveals the location of property that has been concealed from public view, it constitutes a "search" within the meaning of the Fourth Amendment. 410 . A defendant should be allowed to challenge evidence obtained by monitoring a beeper installed in a closed container only if (1) the beeper was monitored when visual tracking of the container was not possible, so that the defendant had a reasonable expectation that the container's movements would remain private, and (2) the defendant had an interest in the container itself sufficient to empower him to give effective consent to a search of the container. Johnson v. United States, 333 U. S. 10, 333 U. S. 14 (1948).

Although there was partial visual surveillance as the automobile containing the can moved along the public highways, the beeper enabled the officers to locate the can in the area of a cabin near Shell Lake, Wis., and it was this information that provided the basis for the issuance of a search warrant. As the plurality recognized in United States v. White, supra, at 749, there is a substantial distinction between "revelation[s] to the Government by a party to conversations with the defendant" and eavesdropping on conversations without the knowledge or consent of either party to it. A holding to that effect would mean that a policeman walking down the street carrying a parabolic microphone capable of picking up conversations in nearby homes would be engaging in a search even if the microphone were not turned on. U.S. 83, 91 Ibid.   The principles for assessing a single person's privacy interests in a particular place, location, or transmission system such as a telephone line, are reasonably well settled.

(1963). Thus, Karo's conviction was upheld. A more difficult case arises when one person's privacy interests fall within another's, as when a guest in a private home has a private container to which the homeowner has no right of access. U.S. 705, 720] On February 6, 1981, agents observed, by means of the video camera, Gene Rhodes and an unidentified woman removing the cans from the locker and loading them onto the rear bed of Horton's pickup truck.

Finally, the ether was removed from the second storage facility by respondent Rhodes and an unidentified woman and transported in Horton's truck, first to Rhodes' house and then to a house rented by Horton, Harley, and respondent Steele.

First, the test proposed by the Court seems squarely inconsistent with Rawlings v. Kentucky, supra. Using the beeper, agents traced the beeper can to another self-storage facility three days later. The Court held: "A person traveling in an automobile on public throroughfares has no reasonable expectation of privacy in his movements from one place to another.

With him on the briefs were Solicitor General Lee, Assistant Attorney General Trott, Elliott Schulder, and Vincent L. Gambale. 2. Compare Katz v. United States, 389 U. S. 347 (1967) (no trespass, but Fourth Amendment violation), with Oliver v. United States, 466 U. S. 170 (1984) (trespass, but no Fourth Amendment violation). U.S. 705, 722] In sum, a privacy interest in the location of a closed container that enters a home with the homeowner's permission cannot be inferred mechanically by reference to the more general privacy interests in the home itself. "Common authority .

710 F.2d 1433 (CA10 1983). [7], The judgment of the Court of Appeals is accordingly. Expectations are formed on the basis of objective appearances, not on the basis of facts known only to others.

6. 438 No prior monitoring of the beeper contributed to this discovery; using the beeper for this purpose was thus untainted by any possible prior illegality. The concurrence section is for members only and includes a summary of the concurring judge or justice’s opinion. 394 The beeper alone told them when the container was taken into private residences and storage areas, and when it was transported from one place to another.   United States v. Jacobsen, 466 U. S. 109, 113 (1984).