Internal auditing must be controlled as must all functions, yet it must be free and sufficiently independent to fulfill its audit role. Control implies constraint, restraint, restrictions on freedom to initiate, to act. Control implies oversight by an authority higher up in a hierarchy. Control implies performance toward a plan and a subsequent appraisal of performance attained, including subjective judgments of the performer.
Bennett, Jerry. 1982. "Control of Internal Auditing as Viewed by the Audit Committee and the CEO." E.C.R.S.B. 1982-1. Robins School of Business White Paper Series. University of Richmond, Richmond, Virginia.