In 2014, Pittsburgh rapper Jamal Knox was sentenced to prison for recording and publishing an anti-cop track called “Fuck the Police.” Less than three years after his conviction, the Supreme Court has agreed to take up an appeal by Knox, who argues his work is protected by the First Amendment.

According to the Associated Press, Knox, aka Mayhem Mal, is asking the court “to set aside his convictions for witness intimidation and making terroristic threats.” The song, which was briefly posted on YouTube, included controversial lyrics that identified officers by name:

“This first verse is for Officer Zeltner and all you FED force bitches and Mr. Kosko can suck my dick for knocking my riches,” Knox raps. “Want beef, well cracker I'm wit it, that whole department can get it/All these soldiers in my committee gonna fuck over you bitches, fuck the police bitch, I said it loud/The fuckin city can't stop me […] I got my glock and best believe dog gonna bring the pump out, and I'm hittin your chest/Don't tell me stop cause I'm resisting arrest.”

According to the Associated Press, Knox recorded the track in 2012, shortly after police found him with 15 bags of heroin, $1,500, and loaded gun. In the months following his arrest, an officer discovered the song online; however, Knox’s attorney has insisted the rapper never intended to intimidate officers, and that he did not post the song himself.

“Just because a police officer arrests you, doesn’t mean you are stripped of any free speech ability to say, ‘Wait a minute, that officer did me wrong, and here’s why I think so,’” Knox’s lawyer Patrick K. Nightingale told the Associated Press.

Knox was convicted along with rapper Rashee Beasley, who was also credited in the song. A judge sentenced Knox to two counts of witness intimidation and two counts of terroristic threats, which, along with his previous drug charges, resulted in a sentence of two to six years behind bars. He was paroled from state prison last month.