We study optimal bank regulation in an economy with aggregate uncertainty. Bank liabilities are used as “money” and hence earn lower returns than equity. In laissez faire equilibrium, banks maximize market value, trading off the funding advantage of debt against the risk of costly default....

Before the crisis, bank regulation relied to a large extent on capital regulation. Liquidity regulation was not widely used. The liquidity problems during the crisis led to calls for liquidity regulation. As a result, the Basel III accord introduced global liquidity standards. An important issue...