Three candidates for Boston's top prosecutor faced off in a tense forum Thursday in Roxbury. Suffolk County District Attorney Kevin Hayden, former Suffolk County District Attorney Rachael Rollins and former Suffolk County Assistant District Attorney Linda Champion made their cases to voters ahead of the Democratic primary. Among the allegations was that Rollins leaked information aiming to sabotage Hayden, then acting district attorney, in his campaign to succeed her, favoring his competitor, then-Boston City Councilor Ricardo Arroyo. "You only know Kevin because I left to become your U.S. attorney," Rollins said Thursday. Champion, a former assistant district attorney in Suffolk County who ran unsuccessfully against Rollins in 2018 and later served as a legal counsel under Hayden, criticized both candidates who have led the office.