To identify questionable bidding practices, the internal audit activity should review the city's contracting files. This review will help determine if the city made efforts to solicit bids from a diverse range of interested firms, ensuring a fair and competitive bidding process. By examining these files, the auditors can identify any patterns of favoritism or irregularities in the awarding of contracts, which are key indicators of questionable bidding practices. This approach is consistent with best practices in auditing procurement processes.

The IIA Standards: Standard 2210 – Engagement Objectives: "Internal auditors must consider the probability of significant errors, fraud, noncompliance, and other exposures when developing the engagement objectives."

IIA Practice Guide: "Auditing the Procurement Function": Emphasizes the importance of reviewing solicitation efforts and contract awards to detect potential irregularities.