Multiple Directorships and Audit Committee Effectiveness: Evidence from Effort Allocation

Recent post-SOX studies have consistently found that the presence of audit committee (AC) directors with multiple directorships is associated with lower financial reporting quality. An implicit assumption of these studies is that AC directors distribute their effort equally across all their directorships. Using a firm size-based proxy and firm risk-based (i.e. probabilities of litigation and of misstatements) proxies to measure relative directorship importance, we investigate (1) whether and how AC directors who serve on multiple AC directorships allocate their effort to different directorships unequally, and (2) whether the unequal prioritization of effort across multiple AC directorships relates to AC monitoring effectiveness. We find a positive (no) relation between the risk-based (firm size-based) directorship importance measures and AC effectiveness, suggesting that AC directors serving on multiple boards unequally allocate their effort to different directorships based on incentives related to firm risk and not to firm size. Our results have relevance for regulators, boards of directors, investors, and other stakeholders.