What is the test for determining whether police misconduct bears "fruit" in a civil case?

But in another category of cases, police misconduct effectively bears no "fruit." See United States v. Cha , 597 F.3d 995, 1003 (9th Cir. 2010). Unreasonable delays fall into this latter category. See id. In those cases, "deterrent value" is only "a necessary condition for exclusion, ... not a sufficient one. The analysis must also account for the substantial social costs generated by the [exclusionary] rule." Davis v. United States , 564 U.S. 229, 237, 131 S.Ct. 2419, 180 L.Ed.2d 285 (2011) (quotation marks and citation omitted). Put another way, a court must determine that "deterrence is worth the price paid by the justice system" before suppressing evidence. Herring , 555 U.S. at 144, 129 S.Ct. 695.