University of Chicago Hospitals v. United States, 545 F.3d 564 (7th Cir. 2008)

(government's position that medical residents are categorically not "students" under I.R.C. § 3121(b)(10) and, therefore, not exempt from FICA tax as a matter of law rejected; case-by-case analysis required to determine whether medical residents qualify for statutory exemption from FICA tax).