This research examines audit fees and auditor’s
opinion of 1,409 listed companies in Thailand from
2004 to 2008 with an attempt to provide evidence on
the impact of economic dependence on auditor’s
independence. Interestingly, the research results
show that firms with unqualified or clean auditor’s
opinion have lower audit fee than those with
modified auditor’s opinions. Modified auditor’s
opinions focus on clean opinion with explanation and
qualified opinion. Such evidence confirms that
auditors who charge high audit fees to their clients
are likely and independently to issue modified
auditor’s report to clients in order to protect their
reputation and avoid litigation risk. Another
explanation may come from additional audit
procedures imposing high audit costs and audit fees
of firms with modified auditor’s opinion. Firms with
uncertainties, going concern, unsolved issues,
misapplication of accounting standards, limitation of
audit scopes by either circumstances or
management are likely to receive modified auditor’s
report. Moreover, this research expects that such
evidence may differ for Big 4 and non-Big 4 auditors
because they may have different economic bond
with audit clients. Big 4 auditors may have greater
audit cost, reputation and litigation risks than nonBig
4 auditors so that they should place more
conservatism and do more audit works when
receiving high audit fee. In contrast, non-Big 4
auditors may want to keep clients who can pay high
audit fee and are likely to issue clean auditor’s report
to please their clients. Further investigation reveals
that both of Big 4 and non-Big 4 auditors are not
influenced by high audit fees in expressing their
opinion. In other words, economic dependence does
not impair auditor’s independence for both Big 4 and
non-Big 4 auditors.