An internal audit procedures manual typically includes detailed information on the methodologies, tools, and techniques used during audits. It also outlines the protocols and guidelines for auditors to follow, including their authority and the scope of their work. Clearly defining the extent of the auditor's authority to collect data from management ensures that auditors understand their rights and limitations, which is essential for carrying out effective and efficient audits.
Reference:
The Institute of Internal Auditors (IIA), Practice Guide on Developing the Internal Audit Manual
"Internal Auditing: Assurance and Advisory Services" by Urton L. Anderson, Michael J. Head, Sridhar Ramamoorti, Chris A . Bailey, and David A. Sarens