Efficiency requires legislative political institutions. There are many ways efficiency can be promoted, and so an ongoing legislative institution is necessary to resolve this choice in a politically sustainable and economically flexible way. This poses serious problems for classical liberal proposals to constitutionally protect markets from government intervention, as seen in the work of Ilya Somin, Guido Pincione & Fernando Tesón and others. The argument for the political nature of efficiency is set out in terms of both Pareto optimality and (...) aggregate welfare maximisation, and similar arguments can be generalised to other social values. (shrink)