Posted June 25, 2014, by Edmund R. Folsom.


In Riley v. California, 573 U.S. __ (June 25, 2014), a unanimous Supreme Court held that, as a general rule, police are required to obtain a warrant before they are allowed to search for data contained in a cell phone seized from a person during an arrest.   Riley involves the consolidated appeal of two cases:  Riley v. California and United States v. Wurie.  In both, police arrested the defendants and searched them incident to their arrests.  Both men were carrying cell phones, which police found and seized.  Riley’s was a smart phone and Wurie’s was a flip phone.   Police conducted warrantless searches of each phone.  In Riley’s case, police found videos and photos that they used to prosecute him for crimes connected to a separate shooting incident.  In Wurie’s case, police found information that allowed them to locate his home, secure a warrant to search the home, seize drugs and other evidence from the home, and use that evidence to prosecute Wurie for possessing and distributing drugs.  Both defendants moved to suppress the evidence found during the warrantless searches of their phones.  Riley’s motion was denied, and the decision was upheld by California’s appellate courts.  Wurie’s motion to suppress was also denied, but the First Circuit Court of Appeals reversed the trial court.  In both cases, the prosecution’s theory was that the “search incident to arrest” exception to the requirement of a search warrant made the warrantless search of a cell phone seized from the defendant’s person, incident to his or her arrest, categorically “reasonable” under the Fourth Amendment to the U.S. Constitution.

The prosecution and the trial courts believed their positions were in line with Supreme Court precedent.  Specifically, in United States v. Robinson, 414 U.S. 218 (1973), the Supreme Court found that it was constitutionally reasonable for a police officer to conduct a warrantless search of an arrestee’s person and the contents of a crumpled cigarette pack located in his coat pocket, based on Robinson’s arrest for operating a motor vehicle after revocation.  The cigarette pack contained capsules of heroin that were used against Robinson in a prosecution for drug possession.  The Robinson Court held that no justification was needed beyond the fact of Robinson’s arrest to render a full search of his person reasonable, and that because the officer found the cigarette pack during a reasonable search incident to arrest the officer “was entitled to inspect it.”   In Riley, the Supreme Court rejected any analogy between searches of cell phone data and the search of Robinson’s cigarette pack.  The Riley Court viewed Robinson as a case that rested on the analysis in Chimel v. California, 395 U.S. 752 (1969).   Chimel had earlier approved of warrantless searches of an arrestee’s person and the area within the arrestee’s immediate control, on grounds that such searches serve the state’s interests in locating weapons that might endanger police and evidence the arrestee might be able to reach and destroy.

The Riley Court had no problem with the searches incident to arrest of either Riley’s or Wurie’s person.  These fit the scope and underlying purposes of Robinson and Chimel.   But the Court found that the additional warrantless searches for data contained in Riley’s and Wurie’s cell phones were not reasonable.   Using a general Fourth Amendment reasonableness analysis, balancing the government’s interests against the degree of intrusion on individual privacy interests, the Riley Court rejected officer safety and destruction of evidence justifications for warrantless cell phone data searches.   The Court pointed out that cell phones themselves present no danger to an officer.  Officers may search phones incident to an arrest to determine whether there is a weapon concealed in the phone or its case, but they cannot generally justify the search of the phone’s electronic contents on officer safety grounds.  As to a destruction of evidence rationale, the Supreme Court rejected the prosecution’s argument that there is a likelihood data will be wiped out by remote if a phone is not searched without a warrant.  The Court pointed out that remote wiping of data can be prevented by turning the phone off, removing the battery, or placing the phone in an inexpensive bag that shields against radio waves.  The Court also rejected the prosecution’s argument that it is more likely, as a general proposition, that a phone’s data will become “locked” and inaccessible if warrantless searches are not allowed.  Against these generally non-existent or marginally served governmental interests in warrantless searches, the Court balanced the intrusion on individual interests involved in a search of cell phone data.  The Court found that the intrusion involved in such searches is far greater than that involved in searching other items typically found on an arrestee, such as a wallet, or papers.  Cell phones contain massive amounts of personal data that make a search of their electronic contents highly intrusive.  The Court found this to be true of Wurie’s relatively unsophisticated flip phone as well as Riley’s smart phone. In this balance, a warrantless search of cell phone data was found to simply be unreasonable.

The Court acknowledged that its decision will impact law enforcement’s ability to combat crime, but flatly stated:  “Privacy comes at a cost.”   In a particular exceptional case, there might be circumstances of particular risk to officer safety or particular risk of evidence destruction if police do not conduct an immediate, warrantless search.    In those circumstances, a warrantless search might be justified by the probable cause and exigent circumstances exception to the requirement of a search warrant.   But absent such case-specific circumstances, the search of cell phone data without a warrant and without probable cause, based on a search incident to arrest theory, is unreasonable.  As put by the Riley Court:  “Our answer to the question of what police must do before searching a cell phone seized incident to an arrest is…simple– get a warrant.”