In this paper we study a political model of capital taxation. Voters w
ho differ in their relative shares of capital and labor income choose
tax policy under majority rule. We compare two political regimes: dire
ct democracy, where the voters vote directly on the policy; and repres
entative democracy, where they elect a representative who then chooses
policy. In both regimes some form of commitment by the voters is nece
ssary to avoid excessive taxation of capital. But the necessary commit
ment under representative democracy corresponds closely to that provid
ed by the actual institutions of most democracies.