Over the years, the U.S. Supreme Court has struggled with the problem of trying to fashion concrete rules on searches and seizures that can be understood and applied by law enforcement officers in the field and in the stationhouse, so officers can have a clear understanding of what they may and may not do under the Fourth Amendment. Just when it looks like a rule is finally refined to the point of general understanding, the court takes an unexpected turn, as it recently did on the subject of searching an arrestee's cell phone incident to his arrest.

The "Search Incident to Arrest" Exception

It's been exactly100 years since the Supreme Court said in Weeks v. U.S. that the Fourth Amendment permits officers "to search the person of the accused when legally arrested to discover and seize the fruits and evidences of crime." And 41 years ago in U.S. v. Robinson, the court said that the right to search incident to arrest includes the right to examine the contents of containers on the arrestee's person or in his immediate possession. Because the justification for this search was that it was incident to lawful arrest, no probable cause was necessary.

Also, the court has held that the Fourth Amendment makes no distinction between "worthy" and "unworthy" containers, meaning that a businessman's attaché case has no greater privacy protection than a beggar's paper bag. As the court has said, "A constitutional distinction between 'worthy' and 'unworthy' containers would be improper. The central purpose of the Fourth Amendment forecloses such a distinction." (U.S. v. Ross) "This court has soundly rejected any distinction between 'worthy' containers, like locked briefcases, and 'unworthy' containers, like paper bags." (Florida v. Jimeno)

Combining these longstanding principles, courts across the country concluded that a cell phone carried by an arrestee could be searched without a warrant, incident to lawful arrest, to the same extent as any other item found in the arrestee's possession. This would seem to be the logical result, given the language in Weeks, Robinson, Ross, Jimeno, and other U.S. Supreme Court decisions. But the court has the ability to alter course and adopt changing rules, for changing times. It has done so on the issue of cell phone searches incident to arrest.

Riley V. California and U.S. V. Wurie

At a traffic stop,David Riley was arrested for possession of loaded and concealed firearms. A search of his cell phone incident to that arrest yielded evidence implicating Riley in an attempted murder and other serious felonies. The evidence from his cell phone was used at trial to convict him on several counts, for which he was sentenced to a term of 15 years to life. On his appeal, he argued that his suppression motion should have been granted as to all evidence seen on his cell phone, and the U.S. Supreme Court unanimously agreed and reversed the convictions.

A second case was decided in the same opinion. After Brima Wurie's arrest for drug sales, officers searched both of his cell phones incident to arrest. Evidence from the search of one of the phones was used to obtain a search warrant for Wurie's residence, from which officers seized 215 grams of crack cocaine, plus other drugs, cash, a firearm, and ammunition. Wurie's convictions netted him a sentence of more than 21 years in federal prison. His convictions were also erased by the U.S. Supreme Court's ruling on the invalidity of warrantless searches of cell phones, incident to arrest.

After tracing the development of the doctrine allowing searches incident to arrest, the court strained to find a way to distinguish searches of cell phones from searches of other property that might be in an arrestee's possession at time of arrest. Finding no other logical basis for carving out a special rule for one particular form of property—namely, a digital data storage device—the court simply looked to the quantity and nature of the private information that could be obtained from searching a cell phone. All nine justices agreed that examination of a cell phone could constitute such a massive invasion of personal privacy that judicial warrants should be required to authorize law enforcement access to them.

Said the court, "Cell phones differ in both a quantitative and a qualitative sense from other objects that might be kept on an arrestee's person. Many of these devices are in fact minicomputers that also happen to have the capacity to be used as a telephone. One of the most notable distinguishing features of modern cell phones is their immense storage capacity."

As examples of information that might be revealed by the search of a cell phone, the court listed private communications, photographs, medical records, Internet searches, bank statements, calendars, text messages, locations and movements, and use of special "apps" indicating the person's interests and concerns. The prospect of routine law enforcement access to so much data of such a personal nature prompted the court to say this: "A search of the information on a cell phone bears little resemblance to the type of brief physical search considered in Robinson. We therefore decline to extend Robinson to searches of data on cell phones, and hold instead that officers must generally secure a warrant before conducting such a search."

Of course, in many arrest situations, officers will not have the probable cause necessary to obtain a search warrant. Riley, in fact, was just such a case. Riley's arrest for carrying a concealed firearm did not provide probable cause to believe his cell phone might contain evidence of an earlier attempted murder as to which Riley was not even a suspect before the cell phone search. The Supreme Court acknowledged and accepted that its ruling would mean that some crimes would go undetected, or unsolved, or unpunished, saying, "We cannot deny that our decision today will have an impact on the ability of law enforcement to combat crime."

Officer Safety Searches

Crooks find waysto convert just about every kind of innocuous object into a disguised weapon. Recognizing this, the court did allow that officers could make a physical inspection of the phone itself (not its data) to ensure their safety. "Officers remain free to examine the physical aspects of a phone to ensure that it will not be used as a weapon."

Other Exceptions

No warrant is required if a cell phone is searched by consent, or under probation or parole search conditions to which the arrestee is subject, or where an imminent exigency necessitates immediate access. As the court said, "Even though the search incident to arrest exception does not apply to cell phones, other case-specific exceptions may still justify a warrantless search of a particular phone."

Other Devices

The rationaleof this decision would also seem to invalidate searches incident to arrest as to other kinds of digital data storage devices, such as laptops, tablets, and smart wristwatches.

No Retroactivity

Admissibilityof evidence obtained from cell phone searches incident to arrest that were lawful in some jurisdictions before issuance of the Riley ruling on June 25, 2014, is not affected by this decision. (Davis v. U.S.)  

Devallis Rutledge is a former police officer and veteran prosecutor who currently serves as special counsel to the Los Angeles County district attorney. He is the author of 12 books, including "Investigative Constitutional Law."