Modeling two Macro policy instruments: Interest rates and aggregate capital requirements

We present a simple neoclassical model to explore how an aggregate bank-capital requirement can be used as a macroeconomic policy tool and how this additional tool interacts with monetary policy. Aggregate bank-capital requirements should be adjusted when the economy is hit by cost-push shocks but should not respond to demand shocks. Moreover, an optimal institutional structure is characterized as follows: First, monetary policy is delegated to an independent and conservative central banker. Second, setting aggregate bank-capital requirements is separated from monetary policy.