Empirical Evidence On Tax Information Sharing Among Sub-Central Administrations

The literature on horizontal tax interdependencies offered limited attention to the interactions on administrative policies although they play an important role in determining the total tax revenues collected. The incentive for sub-central tax authorities to share relevant taxpayer-specific information has been accounted for in the literature on international capital mobility as part of a strategic behavior that trades off cooperation benefits versus competitive gains. In this paper we investigate these issues in a decentralized context with the aim to analyze the determinants of voluntary information sharing between regional tax administrations in Spain. We obtain results that are congruent with standard theory and in particular we find that some specific variables play an important role in determining the willingness of regional tax authorities to share taxpayer-specific information. In particular the presence of reciprocity between two regional administrations is associated with a higher number of tax information shared between them.