Salt Lake County District Attorney Sim Gill has cleared a Salt Lake City police officer who fatally shot a man on Aug. 13, after the man allegedly pulled a knife and threatened to injure officers trying to arrest him.Patrick Harmon, 50, whose most recent address, according to court records from November 2016, was the Road Home shelter, was shot about 10:20 p.m. at 1002 S. State St.A patrol officer had approached Harmon after watching the man ride across all six lanes and a median of State Street, and without a rear red tail light, according to the district attorney’s report, which was released Wednesday afternoon.