The scope of audit committee oversight and financial reporting reliability: Are audit committees overloaded?

Audit committee (AC) responsibilities have been increasing over time, prompting concerns that overloading ACs may impair their effectiveness. Using new measures to capture AC responsibilities based on AC charters, we find that greater AC responsibilities are associated with improved financial statement reliability. Contrary to overload concerns, this association is strongest when ACs have very high levels of responsibilities. Cross-sectional analyses indicate greater AC responsibilities improve financial statement reliability at complex firms, following significant governance lapses, when AC members are capable and experienced, and when ACs also meet often to carry out their oversight duties. Further analysis suggests that our AC responsibility results are driven by duties related to financial reporting while, in stark contrast, allocating responsibilities unrelated to financial reporting to the AC (e.g., risk management) detracts from monitoring effectiveness by decreasing financial statement reliability. The latter is consistent with an overload effect driven by responsibilities that distract the AC from its core financial reporting oversight mandate. Our results inform recent regulatory changes at some exchanges to expand AC oversight