A decade ago, searching someone’s cell phone would give you a list of names and numbers, maybe some recent texts. But now, the average smartphone could contain as much personal and sensitive information as a desktop computer, yet many law enforcement agencies argue they don’t need a warrant to search these devices. That’s why the American Civil Liberties Union has filed suit against the city of San Francisco and its chief of police.

According to the suit [PDF], filed in the Superior Court of California in San Francisco County, a longtime Bay Area activist had pitched a tent and was staging a non-violent protest in Jan. 2012, when he was arrested by the SFPD.

He alleges that police officers seized his phone and not only scrolled through the messages on his phone, but read them aloud.

The California Supreme Court ruled in 2011, in People v. Diaz, that police could search an arrestee’s phone without a warrant and without violating his Fourth Amendment rights. And the Seventh Circuit Court of Appeals held in 2012 that police did not require a warrant to look through a suspect’s phone because it was not password protected.

However, the lawsuit counters that “The California Constitution provides greater privacy protections than the federal constitution… Cell phones today are essentially compact home offices that can be carried on the person or in a briefcase, and searching them poses special privacy concerns beyond what is typical in the search and seizure context. The California Constitution and the First Amendment… also safeguard the rights of free speech and free association against governmental interference, in particular, against the compelled disclosure of speech and associational information.”

The ACLU believes that such warrantless searches go beyond violating the rights of the person being arrested, but also intrude upon the privacy of that person’s “family, friends, co-workers, and anyone whose information is in their phones.”

Speaking to Consumerist about the difference between this lawsuit and the ones that have previously found in favor of warrantless searches, Linda Lye, staff attorney at the ACLU of Northern California, says this lawsuit goes beyond the Fourth Amendment concerns raised in those cases.

“Our case involves privacy claims under California’s more protective constitution, as well as speech and association claims under the federal and state constitutions,” she tells Consumerist. “The Seventh Circuit and other courts haven’t had a chance to examine these claims yet.”

Adds Lye, “The bottom line is that the police shouldn’t be searching through cell phones without a warrant. Phones contain our emails, text messages, information about our health, finances, and personal beliefs. All of that is sensitive information that the cops shouldn’t be able to get without a warrant. Also, a phone contains information not just about its user, but also everyone the user talks to. The Constitution gives us the right to speak our minds and talk to our friends, and to use our phones to do so. That means that the police can’t force me to hand over a list of everyone I’ve spoken to and what I’ve said to them, simply because I’ve been arrested.”

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