Aggregate uncertainty, money and banking

This paper addresses the problem of monitoring the monitor in a model of money and banking with private information and aggregate uncertainty. There is no need to monitor a bank if it requires loans to be repaid partly with money. A market arises at the repayment stage and generates information-revealing prices that perfectly discipline the bank. This mechanism also applies when there exist multiple banks. With multiple banks, competition of private monies improves welfare. A prohibition on private money issue not only eliminates money competition but also triggers free-rider problems among banks, which is detrimental to welfare.