Limits to third-party reporting: Evidence from a randomized field experiment in Norway

Abstract

Third-party reporting and employers’ tax withholding are powerful compliance mechanisms, as long as the employer and employee do not collude to evade. In cooperation with the Norwegian Tax Administration we designed a randomized field experiment with unannounced on-site audits. Matching audit data to administrative registers, we provide evidence of collusive tax evasion. We find that firms assigned to be audited increased their subsequent wage reporting on behalf of their employees by 18 percent relative to firms assigned to the control group. The effect is more pronounced among small firms with few employees. Our results document limitations of third-party reporting, but also that these limitations can be counteracted by minor on-site audits.