In Little v. State, 991 S.W.2d 864, 866 (Tex. Crim. App. 1999), the Court of Criminal Appeals characterized as a Brady claim a contention that the State failed to disclose "the fact that it had lost evidence." Id. A Brady violation occurs when the state: (1) fails to disclose evidence; (2) that is favorable to the accused; (3) that is material in that it creates a probability sufficient to undermine the confidence in the outcome of the proceeding. Thomas v. State, 841 S.W.2d 399, 404 (Tex. Crim. App. 1992). Favorable evidence is any evidence that, if disclosed and used effectively, may make the difference between conviction and acquittal. Id. It includes both exculpatory and impeachment evidence. Id. Exculpatory evidence is testimony or other evidence that tends to justify, excuse, or clear the defendant from alleged fault or guilt. Id. Impeachment evidence is that which is offered to dispute, disparage, deny, or contradict. Id. If the defendant received the evidence in time to use it effectively at trial, his conviction should not be reversed just because it was not disclosed as early as it might have and should have been. Little, 991 S.W.2d at 866. The duty to preserve evidence is limited to evidence that possesses an exculpatory value that was apparent before the evidence was destroyed. Trombetta, 467 U.S. at 489. A defendant must show that the police acted in bad faith to establish that the failure to preserve potentially useful evidence constitutes a denial of due process. Youngblood, 488 U.S. 51, 102 L. Ed. 2d 281, 109 S. Ct. 333. A defendant must also show that the lost evidence was favorable and material. United States v. Valenzuela-Bernal, 458 U.S. 858, 102 S. Ct. 3440, 73 L. Ed. 2d 1193 (1982). A showing that the lost evidence might have been favorable does not meet the materiality standard. Id.