Macroprudential policy uncertainty and implications for leaning against the wind

I consider whether imperfect macroprudential policy can be 'improved' upon by a monetary policy of leaning against the wind. Imperfect macroprudential policy is captured by instrument uncertainty, which leads to tentative and under-responsive macroprudential policy, and model uncertainty, which leads to excessive and over-reactive macroprudential policy. Leaning against the wind by the central bank improves the macroprudential regulator's policy rule if the impact of model uncertainty is stronger than the impact of instrument uncertainty. Such a policy may therefore be pursued in jurisdictions where the macroprudential regulator has low risk-sensitivity and where the efficacy of macroprudential instruments is more certain.