Law of the case doctrine.

From Wike v. Vertrue, 2010 U.S. Dist. LEXIS 90366 (M.D. Tenn. Aug. 30, 2010):

"As most commonly defined, [the doctrine of the law of the case] posits that when a court decides upon a rule of law, that decision should continue to govern the same issues in subsequent stages in the same case.'" Christianson v. Colt Indus. Operating Corp., 486 U.S. 800, 815-16, 108 S. Ct. 2166, 100 L. Ed. 2d 811 (1988) [brackets in original] (quoting Arizona v. California, 460 U.S. 605, 618, 103 S. Ct. 1382, 75 L. Ed. 2d 318 (1983)). Further, "under the doctrine of law of the case, findings made at one point of the litigation become the law of the case for subsequent stages of that same litigation." United States v. Moored, 38 F.3d 1419, 1421 (6th Cir. 1994). "The doctrine also bars challenges to a decision made at a previous stage of the litigation which could have been challenged in a prior appeal, but were not." Rouse v. DaimlerChrysler Corp., 300 F.3d 711, 715 (6th Cir. 2002).