Washington (CNN) Several famous rappers are urging the US Supreme Court to take up a case involving a Pittsburgh rapper and whether his song lyrics are protected under the First Amendment.

In a legal brief filed Wednesday, rappers Killer Mike, Chance the Rapper, Meek Mill, Yo Gotti, Fat Joe, and 21 Savage were among a group of artists and scholars who say Jamal Knox's rap song "F*** the Police" is a "political statement ... that no reasonable person familiar with rap music would have interpreted as a true threat of violence."

"A person unfamiliar with what today is the nation's most dominant musical genre or one who hears music through the auditory lens of older genres such as jazz, country, or symphony, may mistakenly interpret a rap song as a true threat of violence and may falsely conclude a rapper intended to convey a true threat of violence when he did not," they wrote.

Knox performs under the rap name "Mayhem Mal," and together with Rashee Beasley, who goes by "Souja Beaz," formed the rap group "Ghetto Superstar Committee." The two were arrested in 2012 during a routine traffic stop on gun and drug charges.

After their arrest, they wrote and recorded a song titled, "F*** the Police," seen as a homage to the N.W.A. 1988 rap song "F*** tha Police." Knox and Beasley's song, posted on Facebook and YouTube, included the names of the two Pittsburgh officers who arrested them with lyrics like, "I'ma jam this rusty knife all in his guts and chop his feet" and "Well your shift over at three and I'm gonna f*** up where you sleep."

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