Atlanta’s former chief procurement officer—who for more than a decade oversaw billions of dollars in city purchases and public project expenditures—pleaded guilty Tuesday to engaging in a bribery conspiracy in a burgeoning federal corruption investigation of City Hall.

Adam L. Smith, who was Alanta’s chief procurement officer from 2003 until last February, was charged with a single conspiracy count in a criminal information—a form of charge federal prosecutors make in lieu of an indictment that generally signals a plea deal has been reached.