Independent auditors as fiscal gatekeepers

This paper develops a framework for the analysis of gatekeeping in tax enforcement, whereby independent auditors are assigned the duty of attesting taxpayers’ returns. The equilibrium of the market for gatekeepers’ services is characterized, as well as taxpayers’ and auditors’ optimal behavior. The paper identifies the conditions under which the introduction of a mandatory attestation system is likely to be desirable.The results of the paper suggest that: (1) collusion may disrupt the gatekeeping system if the compounded liability of the auditor and the taxpayer is not sufficiently high; (2) a more extended delegation of the enforcement power to private auditors is generally desirable; (3) the cartelization of the gatekeepers’ market has definitely detrimental effects; and (4) when the probability that erroneous attestations are detected and sanctioned depends on the effort exerted by a public enforcer, multiple equilibria may arise, due to the substitutability of public and private monitoring.