Watch: What we know about Tupac murder suspect Duane ‘Keffe D’ Davis

More than 27 years after the fatal shooting of legendary hip-hop artist Tupac Shakur in Las Vegas, one of the long-awaited trials connected to the iconic musician’s murder has officially begun. The 63-year-old defendant, Duane “Keffe D” Davis, a former street gang leader with documented ties to 1990s Los Angeles-area gang conflicts, appeared in court this Monday to formally face the charges against him.

Davis is the only suspect to have gone to trial in the high-profile cold case that has captivated true crime enthusiasts and hip-hop fans across the globe for nearly three decades. Following his indictment by a grand jury last year, legal proceedings moved forward this week, marking a major milestone in a case that has long been shrouded in speculation and unconfirmed reporting. When asked to enter his plea to the murder charge, Davis firmly maintained his innocence and entered a formal not guilty plea before the court.

The killing of Tupac Shakur in September 1996, which occurred after a drive-by shooting following a Mike Tyson boxing match at the MGM Grand Garden Arena, has remained one of the most high-profile unsolved murders in American entertainment history. For years, law enforcement investigations faced roadblocks from witness reluctance and conflicting evidence, leaving the case cold for decades. Davis has long been linked to the case in unofficial reports, and his arrest and trial represent the first concrete legal progress to bring a resolution to the case in a generation.