One of the major confl icts between the principles of democratic politics and the practical reality of expertise in public decision-making takes place in connection with responsibility. The basic principles of democracy include some notion of political responsibility, usually understood to take a bidirectional form, in which the relation between ruler and ruled takes the form of representation and the relation in which the ruled control the ruler takes the form of accountability. The means by which the people assure that the persons who politically represent them are responsible to them vary among democratic regimes. Even within the general framework of representative liberal democracy the character of political responsibility varies considerably, both within a particular regime and between political regimes. Moreover, typically a modem state employs many devices apart from simple parliamentary representation, and very often these devices, such as juries, commissions, independent judges, law lords, and the like predate (or are based on models that predate) parliamentary government. Yet they involve their own notions of responsibility that resolve, ultimately, into a form of political responsibility.