Bill of Attainder

"A bill of attainder is defined to be 'a legislative Act which inflects punishment without judicial trial'"

"...where the legislative body exercises the office of judge, and assumes judicial magistracy, and pronounces on the guilt of a party without any of the forms or safeguards of a trial, and fixes the punishment."

In re De Giacomo, (1874) 12 Blatchf. (U.S.) 391, 7 Fed. Cas No. 3,747, citing Cummings v. Missouri, (1866) 4 Wall, (U.S.) 323.