Tests of controls. Explain what types of control tests an auditor should do in each of the following circumstances and why:

1. The auditor tests controls that contribute to the reliability of accounting systems and concludes they are effective.

2. There are control failures, but in identifying and testing alternative controls the auditor finds them to be effective and therefore concludes that the accounting systems are reliable.

3. The auditor concludes that there are no effective alternative controls that address the transactions and potential errors to which failed controls relate.

4. The control failures and the absence of effective alternative controls cause the auditor to identify a specific risk.