dissenting.
Because I am convinced that the district court’s order barring the use of post-enactment evidence presents a controlling question of law, I would grant the interlocutory appeal and submit the matter to a panel for resolution on the merits.
This Court has previously recognized that the “controlling” nature of a legal question does not depend on whether its resolution will immediately dispose of the litigation. “ ‘Rather, all that must be shown in order for a question to be “con*352trolling” is that resolution of the issue on appeal could materially affect the outcome of the litigation in the district court.’ ” Rafoth v. Nat’l Union Fire Ins. Co. (In re Baker & Getty Fin. Servs., Inc.), 954 F.2d 1169, 1172 n. 8 (6th Cir.1992) (quoting Arizona v. Ideal Basic Indus. (In re Cement Antitrust Litigation), 673 F.2d 1020, 1026 (9th Cir.1981)). Wright and Miller recommend taking a practical view of the “controlling question” requirement, explaining that a question is controlling “if interlocutory reversal might save time for the district court, and time and expense for the litigants.” 16 Charles Alan Wright, Arthur R. Miller & Edward H. Cooper, Federal Practice and Procedure § 3930, at 426 (2d ed.1996).
Under our characterization in In re Baker & Getty Financial Services, and the characterization advanced by Wright and Miller, resolution of the admissibility of post-enactment evidence presents a controlling question inasmuch as resolving the admissibility of post-enactment evidence would dictate the course and duration of discovery in this litigation, as well as the content of any dispositive motions or trial. For example, if this Court determined on an interlocutory basis that the City of Memphis may utilize post-enactment evidence, that ruling would fundamentally shape the nature of the case presented in the district court, and would therefore have a material impact on the outcome of the litigation. In addition, upholding Judge Donald’s certification order would ultimately save the parties time and expense, by avoiding the need for additional discovery and court proceedings if our Court determined after final judgment that a decision to permit post-enactment evidence was not erroneous. I therefore respectfully dissent.