Article I, s. 9 of the U.S. Constitution says that
No bill of attainder or ex post facto Law shall be passed.
Exactly what does and does not qualify as a “bill of attainder” has been difficult to nail down over the years. It hasn’t come up all that often, and when it has, the results have been less than entirely consistent. There’s no bright-line test. But basically, the question is whether the legislature has usurped the judicial function by singling out an identifiable group of people for “punishment.”
Consider one form of the super-tax bill that either has been or will be filed soon:
[Rep. Gary] Peters [(D-MI)] describes his bill as imposing a surtax on bonuses paid by “any company in which the U.S. government has a 79 percent or greater equity stake.”
Well, not much doubt who that one applies to. And one of the definitions of “punishment” under Supreme Court precedent is “the punitive confiscation of property by the sovereign.” So the question boils down to whether the super-tax is “punitive.”
In determining whether punitive or nonpunitive objectives underlie a law, United States v. Brown established that punishment is not restricted purely to retribution for past events, but may include inflicting deprivations on some blameworthy or tainted individual in order to prevent his future misconduct. This view is consistent with the traditional purposes of criminal punishment, which also include a preventive aspect…. Brown left undisturbed the requirement that one who complains of being attainted must establish that the legislature’s action constituted punishment, and not merely the legitimate regulation of conduct.
Someone challenging the super-tax shouldn’t have any trouble finding evidence that the folks in Congress are interested in punishing AIG’s bonus recipients, even setting aside Senator Grassley’s call for them to commit suicide. And though there are cases that declare taxes as non-punitive, a 100% (or close to it) tax might be a different thing — especially with the current Supreme Court. It’s not a slam-dunk either way, but the argument that a 100% tax on pretty much anything is punitive seems pretty strong to me.
I’m writing this on the fly — haven’t got time to do more detailed research. If there’s a reason I’m clearly wrong on this, please let me know. But otherwise, there’s got to be a better way.