INS v. St. Cyr, 533 U.S. 289, 323-24 (2001) (retroactive changes to the immigration consequences of a plea bargain deprives the defendant of "fair notice"); see BMW of North America v. Gore, 517 U.S. 559, 574-75 (1996) (lack of "fair notice" of the scope of civil penalties violates Due Process); Reno v. American-Arab Anti-Discrimination Com., 525 U.S. 471,497-98 (1999) ("AADC") (deportation is a "drastic penalty").