Are there optimal multiple reserve requirements?

A number of developing countries have adopted deficit-finance regimes involving multiple reserve requirements. One question the previous literature on this phenomenon has not addressed is whether multiple-reserves regimes can improve on regimes involving single-currency-reserve requirements if the policy settings of the latter regimes are assumed to be chosen optimally. We find that a \"conventional\" multiple-reserves regime--a regime with positive nominal rates on reservable bonds--cannot Pareto-improve an optimal single-currency-regime but can, in some cases, increase social welfare over such a regime.