Bertha Belligerent does not agree with the United States' policy on nuclear weapons. She organizes a peaceful protest to take place on public land outside of a nuclear testing site. She received the proper permits for her protest and it is rumored that over 1,000 people will be there. The local police are telling the residents of the town not to worry, though. They plan on arresting all the protestors as soon as they show up at the site. Which amendment states that the police can't do this?