A federal judge in Oregon on Monday restricted federal officers from using teargas at protests at the US Immigration and Customs Enforcement (ICE) building in Portland, in response to a lawsuit filed by the American Civil Liberties Union of Oregon on behalf of protesters and freelance journalists.

Michael Simon, a US district judge, issued the preliminary injunction after a three-day hearing in which the plaintiffs – including a demonstrator known for wearing a chicken costume, a married couple in their 80s and two freelance journalists – testified about having chemical or projectile munitions used against them.

The lawsuit, whose defendants include the Department of Homeland Security, argues that federal officers’ use of such munitions is a retaliation against protesters that chills their first amendment rights.