We investigate the monitoring quality of accountants with ties to the Mafia in their role as auditors for “clean” firms—those with no known ties to organized crime. Using a proprietary government database, we identify Italian firms with alleged ties to the Mafia through their executives, directors, or shareholders. We define “suspect accountants” as those who serve as auditors for these Mafia‐connected firms, acknowledging their potential associations with criminal entities. We predict and find evidence that “clean” clients (treatment group) monitored by suspect accountants are more likely to engage in earnings management practices that reduce taxable income, compared with a control sample of “clean” firms monitored by accountants with no known Mafia ties (control group). Our findings suggest that accountants with ties to the Mafia act as low‐quality monitors in the “clean” economy.

We examine how the Big 4 responded to evolving partner qualification requirements in China. By 2017, at least 80 percent of the Big 4 partners were required to hold CICPA qualifications, a requirement that did not apply to local firms. Using data from a 14-year window around the reform, we document that the Big 4 expanded their partnership and primarily complied through internal promotion of locally licensed auditors, often into junior signing roles and serving new clients. Our analyses of audit outcomes yield mixed and time-varying evidence: although we observe relative increases in restatements in selected periods, the triangulated evidence does not suggest a pervasive deterioration in audit quality. However, we find a decline in the Big 4’s market share and audit fee premium. Overall, our findings shed light on how regulatory interventions targeting auditor qualifications reshape audit firms and market competition. Data Availability: Data are available from the public sources cited in the text.