A federal jury in Los Angeles on Monday found that Katy Perry’s 2013 hit “Dark Horse” copied a Christian rap song called “Joyful Noise,” in the music industry’s latest legal battle over copyright infringement.

After a weeklong trial that included testimony by Perry and her longtime producer Dr. Luke, the nine-person jury returned a unanimous verdict that Perry’s song had infringed the copyright of “Joyful Noise,” a 2008 song by the artist Flame, whose real name is Marcus Gray.

The next phase of the trial, to begin Tuesday, will determine the damages owed by Perry and her co-writers, including Dr. Luke, whose real name is Lukasz Gottwald; the star producer Max Martin; Henry Walter, known as Cirkut; Sarah Hudson; and the rapper Juicy J, who performed on the track.