Justice Stevens delivered the opinion of the Court. Much of this case is derived from the precedent set in Carroll v. United States, 267 U.S. 132 (1925), where the Supreme Court ruled that police officers may make a warrantless search of an automobile if they have probable cause to suspect that it contains contraband. This is known as the "automobile exception" to the Fourth Amendment's warrant requirement. The court's reasoning in Carroll v. United States was twofold: First, the "practical mobility" of an automobile made it impractical to take the time to get a search warrant from a magistrate, since in that time the vehicle could leave the jurisdiction. Second, vehicles were presumed to have a lower expectation of privacy than houses or personal containers, since they provide clear visibility of their contents (through the windows), and their primary purpose is the transportation of people instead of the storage of personal property. This particular case dealt with law enforcement officers that tore through the car's upholstery to find illegal liquor in a hidden compartment. The Court had to contrast the "automobile exception" with long standing court decisions which held that portable containers such as suitcases, despite their mobility, are not subject to the same warrantless search as automobiles. The rationale for this is that suitcases and the like are not nearly as mobile as an automobile, and detaining a container while awaiting a warrant is practical. Furthermore, containers are presumed to have a much higher expectation of privacy than vehicles, since their primary purpose is to transport belongings, and most are opaque (some are even locked), which suggests that the owner of a container generally does not expect the contents to be visible or accessible to others. The Court paid much consideration to two previous Supreme Court cases that involved authorities conducting a warrantless search of a vehicle in order to examine the contents of a container inside of the vehicle: United States v. Chadwick, 433 U.S. 1 (1977) and Arkansas v. Sanders, 442 U.S. 753 (1979). In those cases the authorities had first observed containers suspected of containing marijuana outside of a vehicle, where a warrant would be required to search them, and had waited until they were carried into a vehicle, at which point officers took advantage of the "automobile exception" to search the containers inside the vehicle. In those cases, the court found that those searches were