> We also think that the suffering must be socially imposed by due
> process,
This may be what thoughtful retributivists think, but it certainly doesn't capture our pre-theoretical intuitions better than utilitarianism (when Hector kills my buddy, _I_ want to kill him). And I'm pretty sure contractualists are no more able to accommodate our retributive intuitions than utilitarians (Scanlon is quite willing to junk them).
-- Luke