In his theory of public finance, Musgrave (1959) argued that public budgets serve three interdependent functions: (1) the allocation of resources and the financing of public goods, (2) the redistribution of income and (3) the regulation and stabilisation of the economic situation. Since the state's actions to stimulate economic growth have effects on income redistribution, it also has the function of acting on inequality by transferring resources through different social protection regimes. However, the evolution of these regimes over the last 30 years reveals a public intervention characterised by an increasing recourse to the tax system, which has become part of the systems of reconfiguration of the welfare state. Thus, apart from spending programs on a cash basis (transfers to individuals) and in-kind (provision of public services), tax expenditures 1 (Surrey, 1973) are increasingly being added as a third mode of government intervention in social protection (Godbout, 2006;Provencher & Godbout, 2021). Using tax expenditures as a tool for government intervention in social protection has been the subject of multiplying research over the last decade, but there is still limited knowledge about them when it comes to social protection (Morel et al., 2020). This article sheds light on the close links