Should Auditors obtain external confirmations or rely on Confirmations from Auditees?

SA 500 indicates that the reliability of audit evidence is influenced by its source and by its nature and is dependent on the individual circumstances under which it is obtained. Further,

• Audit evidence is more reliable when it is obtained from independent sources outside the entity.
• Audit evidence obtained directly by the auditor is more reliable than audit evidence obtained indirectly or by inference.
• Audit evidence is more reliable when it exists in documentary form, whether paper, electronic or other medium.

Accordingly, depending on the circumstances of the audit, audit evidence in the form of external confirmations received directly by the auditor from confirming parties may be more reliable than evidence generated internally by the entity