We examine the interaction between internal control assessments and substantive testing in a model of fraud detection. The purpose of our study is to examine a two‐stage model of the auditor‐manager interaction in which the auditor assesses the “likelihood” or possibility of fraud in the first stage and conducts substantive tests in the second stage. We examine the allocation of audit resources across these two distinct facets of the audit. We find that, regardless of the auditor's allocation, the probability of undetected fraud remains the same, but the allocation of some audit resources to internal control assessment may provide cost savings for the auditor.

Since the passage of the Sarbanes‐Oxley Act of 2002, many notable frauds have been tied to ineffective audit committee (AC) oversight. As a result, AC oversight is of continuing interest, and regulators continue to debate this issue, garnering a growing body of research focused on the role played by the AC. But little theoretical research exists to guide analytical and empirical researchers investigating AC oversight. The purpose of this study is to provide theoretical guidance by examining AC oversight in a strategic setting. We focus on the AC's role in overseeing internal controls (ICs) and the impact of whether the AC relies on management in designing the controls. We characterize how the nature of control risk changes and how IC strength is associated with the amount of managerial fraud, expected probability of fraud detection (which, on average, equates to audit effort), and audit quality (assessed as 1 − audit risk) across two settings defined by the degree of AC oversight. As one example that highlights the need for theoretical guidance, we consider the literature's presumption that IC strength is negatively associated with audit effort. We find that this association may be positive or negative as IC changes, where the association varies with the degree of direct AC oversight and the change in payoff parameters.

In this study, we provide theoretical guidance for both analytical research and empirical research by considering how changing expectations of earnings affect a dishonest manager's strategy to overstate earnings and an auditor's strategy to exert effort in a two‐period setting. We expect our study's insights on changing economic conditions to help shape future research. We model the manager type as either honest or dishonest, which allows us to differentiate audit risk from audit effort. The key takeaways for future research are the insights on how changes in payoffs and expected earnings affect the associations that involve earnings overstatements and audit effort with audit risk and market price. For instance, researchers typically assume audit effort and audit risk are negatively associated, but we find the association can be positive when, for example, the auditor chooses a period 2 strategy based on the changes in period 1 game parameters. The results of our study provide two additional key insights on the design of future empirical tests. First, by dichotomizing, we show the importance of estimating the intercept in the market pricing equation when studying earnings quality, because market price also adjusts for expected bias through changes in the intercept. Second, our multiperiod setting demonstrates that the effects from a change in the manager's or auditor's incentives in period 1 may reverse in period 2. Empirical studies typically examine the contemporaneous effects of these changes on market price and/or audit risk but fail to identify the cross‐temporal effects we document in our study.

Two distinct lines of research have been dedicated to empirically testing how financial reporting quality (measured as the earnings response coefficient or ERC) is associated with management's choice of reporting bias and with audit quality. However, researchers have yet to consider how ERCs are affected by either the auditor's reaction to changes in the manager's reporting bias or the manager's reaction to changes in audit quality. Our study provides theoretical guidance on these interrelations and how changes in the manager's or the auditor's incentives affect both reporting bias and audit quality. Specifically, when the manager's cost (benefit) of reporting bias increases (decreases), we find that expected bias decreases, inducing the auditor to react by reducing audit quality. Because we also find that the association between expected audit quality and ERCs is always positive, changes in managerial incentives for biased reporting lead to a positive association between ERCs and expected reporting bias. When the cost of auditing decreases or the cost of auditor liability increases, we find that expected audit quality increases, inducing the manager to react by decreasing reporting bias. In this case, changes in the costs of audit quality lead to a negative association between ERCs and expected reporting bias. Finally, we demonstrate the impact of our theoretical findings by focusing on the empirical observations documented in the extant literature on managerial ownership and accounting expertise on the audit committee. In light of our framework, we provide new interpretations of these empirical observations and new predictions for future research.