Research investigating whether auditor-provided tax services are associated
with positive benefits to the firm and / or economic bonding is mixed. Kinney,
Palmrose, and Scholz (2004) suggest that there are benefits to joint provision of
audit and tax services by audit firms on the basis of evidence that financial statement
restatements are less frequent when auditors also perform clients’ tax work.
Omer et al. (2006) provide evidence that, prior to SOX, tax fees paid to auditors
are associated with reductions in ETRs, but this relation weakens after SOX. They
also find a positive association between tax fees paid to auditors and unexpected
audit fees (based on firm size and risk characteristics), offering support for economic
bonding, a concern of the PCAOB that firms use nonaudit service fees such
as tax fees to compel their auditors to acquiesce to aggressive financial reporting
and issue clean audit opinions