On February 24th, a small group of University of Washington students gathered on the 45th street overpass above Interstate 5, carrying a 30-foot banner, which read “Education not incarceration.”

After an hour of perfectly legal protesting—you’re allowed to assemble on overpasses, as long as you don’t hang signs from the freeway and aren’t blocking traffic—the students were getting ready to head home when a Washington State Patrol Officer arrived on scene.

“We heard the woop woop [of the siren],” says UW student Jamie Brown, 27. According to Brown, State Trooper Douglas Power told the group to take their sign down and move on. “He wouldn’t or couldn’t tell us what law we were breaking,” Brown says.“He was saying it was a safety issue, that we were threatening people on the freeway.”

Next, Brown says the Trooper grabbed one of the students and pulled the sign down on top of the group. The entire incident was caught on tape.

The State Patrol is pretty candid about the Trooper’s conduct. “When the trooper got there, he thought there was a hazard of the sign possibly blowing into the lanes of I-5,” says State Patrol Spokesman Bill Gardiner. “He probably overreacted.”

According to Gardiner, the demonstration “should have been ok” since nothing was affixed to the overpass, and he blames Power’s behavior on a lack of experience. “[He] may not have developed that skill of defusing things,” Gardiner says. Because of the incident, Power will receive additional training and a record of the incident will be added to his personnel file.

Several of the students say they will be filing complaints with the Washington State Patrol.