In a dynamic economy whose government is interested in both equity and
efficiency, time consistency problems arise even if the government ha
s access to nondistortionary tax instruments. Moral hazard in producti
on leads to a non-degenerate distribution of income, which the governm
ent would like to ''flatten'' ex post. Self-enforcing social agreement
s can mitigate the tendency toward excessive redistribution. We invest
igate the nature of the distortions caused by the time consistency pro
blem, and show that in the constrained-optimal equilibrium, usually a
linear tax schedule is imposed. This remains true if renegotiation of
the social agreement is possible. (C) 1997 Academic Press.