We analyze the problem of the choice of a central bank constitution. We model the decision problem as a choice behind a veil of ignorance in which the policy maker only receives information about predicted behavior under different policies. The policy maker is informed about (probability distributions of) consumers’ behavior and the distribution of productivity shocks but does not know consumers’ interpersonally comparable utility functions. Starting from a representation theorem for the policy maker’s preferences over policies, we compare price stabilization, output stabilization, and inflation targeting in a standard new Keynesian model with Calvo price staggering. Surprisingly, under our policy criterion, the policy maker perceives a tradeoff between output stabilization and price stabilization. The reason is that in the absence of knowledge about cardinal utility functions, stabilizing the natural level of output is not normatively desirable. We find that the policy maker puts a higher emphasis on price stability than output stability if price staggering is low, intertemporal discounting is high, intertemporal substitutability is low, or substitutability between goods is high.