Macroprudential Regulation Versus Mopping Up After the Crash

This paper compares ex-ante policy measures (such as macroprudential regulation) and ex-post policy interventions (such as bailouts) to respond to financial crises in models of financial amplification, i.e. models in which falling asset prices, declining net worth and tightening financial constraints reinforce each other. The optimal policy mix in such models involves a combination of both types of measures since they offer alternative ways of mitigating binding financial constraints. Comparing their relative merits, ex-post policy interventions are only taken once a crisis has materialized and are therefore better targeted, whereas ex-ante measures are blunter since they depend on crisis expectations. However, ex-post interventions distort incentives and create moral hazard. This introduces a time consistency problem, which can in turn be solved by ex-ante policy measures. Limiting ex-post transfers to the revenue accumulated in a bailout fund reduces welfare.