Final answer:
When there is no audit trail for a specific procedure, auditors can use compensating controls, increase reliance on substantive testing, or employ data analytics techniques.
Step-by-step explanation:
When the test of controls for a specific procedure leaves no audit trail, the auditor needs to implement alternative controls to ensure the accuracy and reliability of the audit findings. Compensating controls are additional procedures or measures put in place to achieve the same objectives as the procedure with no audit trail.
Another control that can be utilized is increased reliance on substantive testing. Substantive testing involves directly testing the account balances or transactions to obtain audit evidence. By performing more substantive testing in the absence of an audit trail, the auditor can still gather sufficient evidence to support their conclusions.
Lastly, the auditor can consider analyzing other sources of data or using data analytics techniques. This can involve examining related information or using advanced data analysis tools to identify any anomalies or patterns that may indicate weak controls or potential errors.