The Effect of Joint Auditor Pair Composition on Audit Quality: Evidence from Impairment Tests

Using a sample of firms from France, where the law requires the use of two auditors, we study the effect of auditor pair composition on audit quality by examining a specific account, goodwill impairment. We document that firms audited by a Big 4-non-Big 4 auditor pair (BS) are more likely to book an impairment and book a larger impairment than firms audited by a Big 4-Big 4 auditor pair (BB) when low performance indicators suggest a greater likelihood of impairment. Moreover, firms audited by a BB pair reduce impairment disclosures when they book impairments, while firms audited by a BS pair do not, suggesting lower transparency for firms audited by a BB pair. Our results inform investors and firms in mandatory joint audit regimes, as well as regulators who are considering requiring joint audits.