We find mixed support for the effectiveness of SOX. Specifically, for firms
that would miss their earnings targets absent ETR changes, higher tax fees paid to
auditors are associated with greater third-to-fourth-quarter ETR reductions in the
pre-SOX period, and this relation holds in the post-SOX period. This negative
association does not exist for firms that would otherwise meet or beat their consensus
earnings forecasts either before or after the passage of SOX. However, we also
discover that, for firms not purchasing tax services from their auditors, the negative
association between third-to-fourth-quarter ETR changes and missing income
goals absent ETR changes that exists in the pre-SOX period cannot be reliably
demonstrated in the post-SOX period. This result provides some support for Maydew
and Shackelford’s 2006 suggestion that SOX produces higher quality audits
(which, in the context of our study, we interpret to mean less opportunistic thirdto-
fourth-quarter ETR changes).