BOSTON (AP) — A former Boston high school dean serving a 26-year sentence in state prison for shooting a student he recruited to deal drugs has been sentenced to an additional 18 years or more on a federal gang-related charge. Prosecutors say Shaun Harrison, 63, lived a double life, portraying himself as a mentor for troubled teens while hiding his own gang ties and luring students into drugs and violence. Harrison pleaded guilty last year to a count of racketeering conspiracy. He’s already serving time after his 2018 conviction for attempting to kill a student who was selling marijuana in the high school at Harrison’s direction.