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, "[u]nder 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).

Applying the law of the case doctrine to a court's prior ruling is a discretionary tool meant to promote judicial efficiency. Omimex Energy, Inc. v. Blohm, 2010 U.S. App. LEXIS 8009, 2010 WL 1431320 at *8 (6th Cir. 2010). "Nevertheless, a court's power to reach a result inconsistent with a prior decision reached in the same case is 'to be exercised very sparingly, and only under extraordinary conditions.'" In re Kenneth Allen Knight Trust, 303 F.3d 671, 678 (6th Cir. 2002)(citation omitted). Extraordinary circumstances which allow for reconsideration of an issue previously decided include where substantially different evidence is presented, there is subsequent contrary and controlling authority, or where the underlying determination is clearly erroneous and would work a manifest injustice. United States v. Rayborn, 495 F.3d 328, 337 (6th Cir. 2007).