O.K.
But this isn't really a bill of attainder then. We are talking about a decision relating to the Constitutionality of a law.
And in cases of impeachment, the Senate sits as a jury and the House brings the Charges. Is an impeachment then, by definition, a bill of attainder?
trying impeachment cases is a right granted to the Senate by the Constitution. Overturning judicial decisions isn't.