WASHINGTON (AP) — President Donald Trump on Monday signed an executive order requiring the Justice Department to investigate and prosecute people for burning the American flag, an activity that the U.S. Supreme Court has ruled is legitimate political expression protected by the U.S. Constitution.

The order the Republican president signed in the Oval Office acknowledged the court’s 5-4 ruling in a case from Texas in 1989, but said there is still room to prosecute flag burning if it “is likely to incite imminent lawless action” or amounts to “fighting words.”

“You burn a flag, you get one year in jail. You don’t get 10 years, you don’t get one month,” Trump said. “You get one year in jail, and it goes on your record, and you will see flag burning stopping immediately.”

The order also called for Attorney General Pam Bondi to pursue litigation to challenge the 1989 ruling, an attempt by Trump to get the issue back in front of the Supreme Court. Today’s Supreme Court is much more conservative than the makeup of the court in 1989 and includes three Trump-appointed judges.

Civil liberties advocates and constitutional scholars questioned both the legality and the merit of Trump’s action.