The authority of the internal audit activity, as outlined in the audit charter, includes having full access to the organization's records, physical property, and personnel necessary to conduct audit engagements. This access is critical for the internal audit activity to perform its duties effectively and independently, ensuring that auditors can obtain the information and resources they need to evaluate the organization's processes and controls comprehensively.

The IIA Standards: Standard 1000 – Purpose, Authority, and Responsibility: "The purpose, authority, and responsibility of the internal audit activity must be formally defined in an internal audit charter... The chief audit executive must periodically review the internal audit charter and present it to senior management and the board for approval."

The IIA Practice Guide: "Understanding the Importance of the Internal Audit Charter": Emphasizes the necessity for the internal audit activity to have unrestricted access to organizational records, property, and personnel.