Currently, there are two main types of payment instruments: cash and deposit-based electronic payments. Cash is a liability of the central bank and is perceived to be very safe. Deposits are liabilities of commercial banks; they are normally safe but are subject to default risk in times of crisis. As the economy becomes increasingly cashless, can we rely on the private sector to invest in the optimal level of safety in the electronic payment system?
We answer this question by modelling private incentives to invest in safety in a deposit-based payment system. Depositors can mitigate the risk in the system through monitoring to reduce the risk of default before it happens (ex ante) or through monitoring for timely detection of defaults after they’ve occurred (ex post). In addition, they can also set up a separate, safe account as a backup to receive funds from the risky account in a crisis situation.
We find that because depositors do not internalize the externalities in the payment system, the private sector can over- or under-adopt the use of safe accounts. However, governments could use taxes or subsidies to correct private incentives and restore the optimal adoption of safe accounts.