Washington (CNN) The Supreme Court struck down part of a federal law that denies trademark protection of terms that disparage living or dead.

The ruling could benefit the NFL's Washington Redskins, whose trademark was canceled based on the same law in a separate proceeding.

"Holding that the registration of a trademark converts the mark into government speech would constitute a huge and dangerous extension of the government-speech doctrine, for other systems of government registration (such as copyright) could easily be characterized in the same way," Justice Samuel Alito wrote in the majority opinion.

"The commercial market is well stocked with merchandise that disparages prominent figures and groups, and the line between commercial and non-commercial speech is not always clear, as this case illustrates," Alito added. "If affixing the commercial label permits the suppression of any speech that may lead to political or social 'volatility,' free speech would be endangered."

The case at hand involves Simon Tam, an Asian-American musician and political activist who named his rock band "The Slants" in an attempt to take back a term that once directed as an insult. He sought to register the name with the trademark office.

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