SAN FRANCISCO (CBS / AP) — The American Civil Liberties Union filed a lawsuit on Wednesday claiming that the San Francisco police conducted a search of an activist’s cellphone without a warrant.

The civil suit claims that two San Francisco police officers violated Bob Offer-Westort’s privacy when they searched his cellphone after he was arrested last year for protesting a proposed city ordinance he felt was unfairly targeting homeless people.

The ACLU argues that the warrantless searches violated Offer-Westort’s freedom from unreasonable search and seizure and his freedom of speech. The suit also says the constitutional rights of his family, friends and co-workers and the information in their phones were also violated.

The group claims that is the first civil suit in California to challenge warrantless cellphone searches at the time of arrest.