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Riley v. California (Amicus Brief)

In this amicus brief, the Brennan Center argues that law enforcement officers should not be allowed to search the contents of a cellphone without a warrant.

Published: March 11, 2014

In Riley v. California, San Diego police officers pulled over David Leon Riley for driving with an expired license plate. The police found firearms in his car, placed him under arrest and seized his cellphone. The police subsequently went through and downloaded data from his phone without a warrant while “looking for evidence.” Prosecutors relied on pictures and videos found on the cellphone to support their allegation that Riley had committed crimes for the benefit of a criminal street gang, exposing Riley to a significantly enhanced sentence.

When the police arrest someone, they are allowed to search the person’s body for weapons and evidence. But whether they can also rummage through the contents of the person’s cellphone – including his or her text messages, e-mails, call-logs, pictures and videos – without a warrant is something the Supreme Court will confront in this case. Riley is poised to set another baseline for privacy and Fourth Amendment protection in the digital age. 

Both the trial court and the California Court of Appeal upheld the admissibility of the evidence from Riley’s cell phone. Both courts relied on a previous California Supreme Court decision ruling that searches of an arrestee’s cellphone are covered by the ‘search incident to arrest’ doctrine – a decades-old exception to the Fourth Amendment that permits police to search a person during or shortly after the arrest without a warrant in order to obtain weapons that could harm the officer or destructible evidence.

Riley petitioned the U.S. Supreme Court for certiorari. In January 2014, the Supreme Court agreed to hear the case along with United States v. Wurie, another case where the government claimed the right to search through a person’s cellphone call logs incident to arrest.

The Brennan Center, along with the National Association for Criminal Defense Lawyers, filed an amicus brief in support of Mr. Riley, urging reversal of the lower court’s decision. The brief argues that a warrant requirement is necessary to ensure appropriate judicial oversight over all searches of cellphones, which can contain vast quantities of sensitive information about a person’s life. Once in the hands of law enforcement, such data can be kept on government databases and shared among numerous agencies and officials for years, sometimes decades. Given the enormous privacy implications of cellphone searches, questions about what evidence the police can search for on a cell phone, for what purpose and for how long should be decided by a neutral and detached magistrate, not a cop in the heat of an investigation.  

  • Download the amicus brief here

Merits Briefs 

Certiorari-Stage Briefs

Amicus Briefs Supporting the Petitioner Riley

Amicus Briefs Supporting Neither Party


Riley v. California Amicus Brief