A new lawsuit is arguing that warrantless cellphone searches at the time of arrest violate individuals’ and their associates’ right to privacy, right to be free from unreasonable searches and seizures, and right to free speech and association under the California Constitution as well as the right to free speech and association under the First Amendment.

Pillsbury and the American Civil Liberties Union Foundation of Northern California filed a lawsuit against the city and county of San Francisco and Chief of Police Greg Suhr on behalf of Robert Offer-Westort, a civil rights activist whose cellphone was searched after he was arrested while engaging in an act of nonviolent civil disobedience.

“Cellphones contain a wealth of personal information not just about the person who owns the phone, but about everyone with whom they communicate," said Marley Degner, a senior associate in Pillsbury’s litigation practice in San Francisco. "Just as the police would need a warrant to search our home office, they should be required to get a warrant to search our cellphones."