You know you might be subject to a bill of attainder when . . .

. . . there's a law with your name on it, as this DC Circuit opinion confirms. Bills of attainder are prohibited by Art. I, Sec. 9 of the Constitution. A leading modern case on bills of attainder is United States v Lovett, 328 US 303 (1946), for anyone who's interested. (from How Appealing)