Balesteri, assigned to a gang enforcement unit, and partner Bradley Ruzak stopped Mack shortly after midnight Aug. 11, 2015, after the two cars passed one another in the 5700 block of South Throop Street. The two officers said in reports and testimony that they noticed Mack was not wearing a seat belt and that his red Jeep Cherokee was missing its front license plate. Police reports filed in the case said Mack, then 18, acknowledged he belonged to the Gangster Disciples street gang.