The U.S. government can’t reject trademarks that some people might find disparaging or offensive, a federal appeals court ruled Tuesday, citing constitutional free-speech protections.

The U.S. Court of Appeals for the Federal Circuit in Washington struck down a nearly 70-year-old provision in federal law and sided with Simon Tam, the frontman for the Asian-American rock band the Slants. Tam had sought to register the band’s name, but a U.S. Patent and Trademark Office examiner denied the registration, saying the phrase was likely disparaging to people of Asian descent.

The ruling could help the Washington Redskins football team, which is fighting a 2014 Patent and Trademark Office decision to cancel its trademarks because Native Americans found the name disparaging. The team’s case is in a different court, but the Redskins are making the same legal argument as Tam.

Tuesday’s decision endorsed a robust view of the First Amendment as it struck down a part of the 1946 Lanham Act that barred the registration of disparaging trademarks. The appeals court also acknowledged its ruling opened the door for the registration of trademarks that contain ethnic slurs and “offend vulnerable communities.”

“Whatever our personal feelings about the mark at issue here, or other disparaging marks, the First Amendment forbids government regulators to deny registration because they find the speech likely to offend others,” Judge Kimberly Moore wrote for the court’s majority. She said the Constitution protects free speech “even when speech inflicts great pain.”

One dissenting judge, Alan Lourie, said the court wrongly interfered with long-standing congressional policy of giving the Patent and Trademark Office authority to “filter out certain undesirable marks” from the federal trademark registration system. The court’s decision to overturn past legal precedent and invalidate the provision would “further the degradation of civil discourse,” the judge said.

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