United States v. Jacobsen

The Fourth Amendment regulates governmental, not purely private, action. Although sealed packages ordinarily carry a legitimate expectation of privacy, the Federal Express employees independently opened this package and examined its contents. Their conduct therefore did not itself trigger the Fourth Amendment, even if a government search on the same facts might have required a warrant.

When government action follows a private search, its legality depends on whether it exceeds the scope of the privacy invasion already accomplished by the private party. The government may use information that a private party has revealed because the owner's expectation of privacy in that information has already been frustrated.

The agent learned nothing new by moving aside the newspaper, removing the tube, taking out the bags, and visually inspecting the powder. The employees had already discovered the package's only significant contents and had specifically invited the agent to see them. Reexamining what the private search had exposed merely reduced the risk that the employees' report was mistaken; it did not invade an unfrustrated privacy interest.

A seizure of property occurs when the government meaningfully interferes with possessory interests. The agents seized the package when they asserted dominion and control over it for law-enforcement purposes, even though Federal Express was then physically holding it.

The private search had revealed a suspicious tube, nested plastic bags, and white powder, and the employees' report matched what the agent could observe. Respondents conceded that the agents had probable cause to believe the package contained contraband.

Given the prior opening of the package, the exposure of its contents, and the virtual certainty that the tube and bags held contraband and little else, the package could not support a justifiable privacy interest comparable to that in an ordinary closed container. A warrantless temporary seizure based on probable cause was therefore reasonable.

The chemical test exceeded the employees' private search because they had not tested the powder. But an investigative act is a Fourth Amendment search only if it infringes an expectation of privacy that society recognizes as legitimate.

The test was tightly limited: it disclosed only whether the powder was cocaine, not its composition if it was not cocaine and not information about any lawful item. Society does not recognize a legitimate privacy interest in possessing cocaine, a substance Congress has prohibited.

The Court treated the test as analogous to the dog sniff in United States v. Place. Like a properly limited narcotics sniff, the test was designed to disclose only the presence or absence of contraband, rather than exposing lawful personal effects to government inspection.

The test did affect possessory interests because it consumed a trace amount of the powder. This converted the prior temporary detention of the property into a permanent deprivation of that small sample.

The Court balanced the slight intrusion against the government's substantial interest in quickly determining whether the suspicious material was contraband. The packaging and circumstances made it virtually certain that the powder was cocaine.

Only a minute quantity was destroyed, apparently too little for respondents even to notice, and the package had already been lawfully detained. Requiring a warrant would have added little protection to Fourth Amendment interests, so the seizure was reasonable.