Since 2007, and especially over the past year, actions of public officials have blurred the lines between monetary and fiscal policy almost beyond recognition. Central banks have expanded both the scope and scale of their interventions in unprecedented fashion. This fiscalization risks central bank independence, thereby weakening policymakers’ ability to deliver on their mandates for price and financial stability. In our view, to find a way to back to the pre-2008 division of responsibilities, officials must establish clearer limits on what central banks can and cannot do.

In that division of official labor, it is fiscal authorities that ought to make the unavoidably political choices that directly influence resource allocation. And governments should not conceal such fiscal actions on the balance sheet of the central bank. In a democracy, doing so lacks legitimacy and would become unsustainable….