What is the test for abuse of abuse of the courts in cases involving drug dealing and drug dealing?

Appellants also claim the district court erred in admitting testimony of prior drug transactions between defendants. We review the court's decision on this point for abuse of discretion. United States v. Sitton, 968 F.2d 947, 958 (9th Cir.1992), cert. denied, 113 S.Ct. 478 (1992), and cert. denied, 113 S.Ct. 1306 (1993).

Evidence of other crimes or acts relevant to an issue in the trial may be admitted consistent with FRE 404(b), except "where the evidence proves only the defendant's criminal disposition." United States v. McKoy, 771 F.2d 1207, 1213 (9th Cir.1985) (emphasis in original). Evidence of prior crimes may be relevant in conspiracy cases, for example, "to show the background and development of the conspiracy." Id. at 1214, citing United States v. Nadler, 698 F.2d 995 (9th Cir.1983).