Evidence of a Nonlinear Association between Auditor-Provided Non-Audit Services and Audit Quality

This study examines the possibility of a nonlinear association between auditor-provided non-audit services (NAS) and audit quality. The effect of NAS on audit quality has been a long-standing debate among academics and regulators. One view is that NAS can potentially create economic bonding between the auditor and client, lowering audit quality. Another view is that NAS creates knowledge spillover, improving audit quality. Our unique approach provides evidence of a nonlinear association between NAS and audit quality, where client misstatement rates are higher for audit offices with both high and low levels of NAS. We also find a nonlinear association between NAS provision and both missed material weaknesses and meeting or beating analysts’ consensus forecast by a small amount. This study should be of interest to audit firms, audit committees, and regulators because it advances our understanding of the effects of NAS on audit quality.