In this paper I defend a liberal theory about how legal rules can and ought to be interpreted. The theory emerges from a critical examination of H. L. A. Hart's influential views on the limited but unavoidable indeterminacy of legal rules. I begin with a brief sketch of Hart's early theory (as it is traditionally understood) offering various suggestions as to how it might usefully be modified. Next, several possible objections to my modifications are sketched and criticized. Finally, reasons are (...) provided for supposing that the modified theory may well represent Hart's current position. (shrink)