Should bank capital regulation be risk sensitive?*

We present a screening model of the risk sensitivity of bank capital regulation. A banker funds a project with uninsured deposits and costly capital. Capital resolves a moral hazard problem in the choice of the probability of default (PD). The project's loss given default (LGD) is the banker's private information. The regulator receives a noisy signal about the LGD and imposes a minimum capital requirement. We show that the optimal sensitivity of capital regulation is non-monotonic in the accuracy of risk assessment. If the signal is inaccurate, the regulator should use risk-insensitive capital requirements. Given sufficient accuracy, the regulator should separate types via risk-sensitive capital requirements, reducing the risk-sensitivity of bank capital as accuracy improves.