United States: Supreme Court Prohibits Warrantless Mobile Phone Searches, Underscores Individual Right To Privacy

The Supreme Court of the United States released a unanimous decision last week barring law enforcement from searching the mobile phones of individuals placed under arrest without first obtaining a search warrant or the arrestee's consent.  In each of two companion cases, Riley v. California and United States v. Wurie (the latter arising from a federal prosecution in Massachusetts), police officers detained a suspect, placed the suspect under arrest and then searched a mobile phone that was on the suspect's person without consent or a warrant.  Officers did so under a longstanding exception to the warrant requirement covering searches "incident to arrest."  While the Constitution of the United States generally requires either a valid warrant or voluntary consent before officers can search one's person, home and other effects, the "search incident to arrest" exception has allowed law enforcement to search an arrested person and his immediate effects (such as pocket contents) as a matter of course—with the justification that such searches help to ensure officer safety and prevent destruction of evidence.

The unanimous Supreme Court ruled that the "search incident to arrest" doctrine does not allow routine searches of mobile phones taken from an arrestee's possession.  It found that less intrusive measures—such as physically examining a phone's exterior for potential safety threats and securing it out of the arrestee's (physical and digital) reach to prevent wiping of its contents—would adequately address law enforcement concerns.
The Supreme Court flatly rejected the contention that searching a mobile phone is "materially indistinguishable" from searching other physical items on one's person, such as a wallet, address book or purse.  The Supreme Court noted that comparing a search of those types of physical objects to a search of a mobile phone "is like saying a ride on horseback is materially indistinguishable from a flight to the moon ... Modern cell phones, as a category, implicate privacy concerns far beyond those implicated by the search of a cigarette pack, a wallet, or a purse."

The Supreme Court's decision to exclude mobile phone searches from the "search incident to arrest" doctrine does not mean officers are always precluded from accessing phone contents.  Most importantly, officers still may seek consent to search an arrestee's phone and act on such consent if given.  The Supreme Court also suggested that officers could access a phone's contents to the extent necessary to disable auto-locking features that would render the phone inaccessible later on once a warrant had been obtained.  Finally, it left open the possibility that case-specific "exigent circumstances" might justify certain warrantless phone searches without consent.

Mobile Phones Raise New Privacy Concerns

As the "flight to the moon" comment above suggests, the Supreme Court rooted its decision in a determination that the storage capacity of a mobile phone is vastly greater than any other physical object a person typically carries and, thus, privacy considerations with respect to mobile phones are different than those applicable to other physical objects one carries.  The Supreme Court outlined four factors that make mobile phones unique:

  1. Mobile phones collect several distinct types of information, which taken together can reveal more than each of them could separately.  The Supreme Court noted that even the applications (apps) on one's phone reveal a great deal of personal information that would be unavailable from a search of one's person.
  2. Each specific type of information on a mobile phone is more detailed than what would be available through a search of other physical objects.   For example, instead of an officer looking through a few pictures in a wallet, a mobile phone can hold thousands of photos, along with the dates and locations of each image.
  3. A mobile phone can give an entire chronology of all communications with other persons, which can go as far back as the date of purchase of the phone, or even earlier.
  4. Finally, mobile phones, which contain what the Supreme Court describes as "a cache of sensitive personal information," are pervasive in modern life: it is the exception that the average American does not have a cell phone on or near their person at almost all times.

In sum, the Supreme Court's decision recognizes the significance of an individual's expectation of privacy in content stored on or accessible through mobile phones in a way that creates the potential for many spillover effects into other contexts—such as the collection, storage and brokering of a user's web browsing or other digital data without clear user consent to do so. 

Application to Individuals

For clients facing white collar investigations by the U.S. Department of Justice or another law enforcement agency, this decision may mean they will be better able to object to providing data stored on mobile devices.  As a practical matter, however, clients often seek to be cooperative, so they likely would consent in any event.  By contrast, in situations where company representatives or individual executives may be facing imminent arrest, they should consult with an experienced white collar defense lawyer before offering law enforcement officers statements or consent to search a mobile device.  One can always decide to cooperate after consulting with counsel, but it may be impossible to undo damage caused by a statement made or search consent given before such consultation has occurred.  In addition, to the extent the law enforcement officer seeks to invoke one of the "exemptions" addressed by the Supreme Court's decision, the executive or company representative who is under arrest should ask the officer to simply secure the phone without accessing its contents until he or she can consult with a lawyer about giving search consent.  To the extent the officer insists upon taking steps designed to ensure future access (e.g., disabling the auto-lock feature), the executive should request that the officer take all such actions only while the executive is watching, to ensure the actions taken indeed are limited to those necessary to accomplish the stated purpose.  

Application to Employers

Given that the Supreme Court's decision is grounded in the Fourth Amendment, some may argue that it is not directly applicable to the private workplace context.  However, federal courts historically have been willing to rely upon Fourth Amendment precedent when deciding analogous issues in the private employment context, particularly in cases where there may be little other relevant precedent.  As a result, because this decision clearly signals a more pro-privacy approach to mobile device use, employers should re-examine their current policies that address employees' use of mobile devices.  At a minimum, employers should have policies that clearly spell out expectations with respect to privacy and mobile phone use and that address procedures for commonly encountered workplace issues, including dual-use devices (those that are used for both personal and business use), reviewing mobile device contents in connection with internal investigations, activating litigation holds, and procedures for handling mobile devices and their contents in cases of departing employees.

Finally, when it comes to inspections and monitoring of mobile devices in the workplace, in light of the Supreme Court's decision, employers should:

  • Consider providing clear notice to employees regarding the potential for inspections and monitoring of mobile devices used for work
  • Ensure they have defensible and legitimate business interests in conducting the monitoring (similar to law enforcement having legitimate interests in conducting permissible searches)
  • Consider effective ways to obtain consent of employees prior to inspecting or monitoring contents of mobile devices used for work-related purposes

Following these practical tips can help balance individual privacy rights, while at the same time allowing employers to protect legitimate business interests in light of the Supreme Court's decision.

Supreme Court Prohibits Warrantless Mobile Phone Searches, Underscores Individual Right to Privacy

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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