Petrov v. Gonzales, 464 F.3d 800, 2006 WL 2846451 (7th Cir. Oct. 6, 2006) (question whether conviction constitutes a particularly serious crime, under 8 U.S.C. 1252(a)(2)(C), precluding political asylum or withholding of deportation, is held to be a discretionary decision not subject to petition for review jurisdiction in the court of appeals).

http://caselaw.lp.findlaw.com/data2/circs/7th/054696p.pdf