Optimal Financial Crises

Empirical evidence suggests that banking panics are a natural outgrowth of the business cycle. In other words panics are not simply the result of quot;sunspotsquot; or self-fulfilling prophecies. Panics occur when depositors perceive that the returns on the bank's assets are going to be unusually low. In this paper we develop a simple model of this type of panic. In this setting bank runs can be incentive-efficient: they allow more efficient risk sharing between depositors who withdraw early and those who withdraw late and they allow banks to hold more efficient portfolios. Central bank intervention to eliminate panics can lower the welfare of depositors. However there is a role for the central bank to prevent costly liquidation of real assets by injecting money into the banking system during a panic