Thx!
US court of appeals - 6th Circuit
US v Reynolds - I am not finding anything about 95% accuracy rate being rejected. Only support of the district courts decision, which found the maps reliable.
We review a district court’s “admissibility decision” for an abuse of discretion. United States v. Gissantaner, 990 F.3d 457, 463 (6th Cir. 2021). We see no such abuse here.
This case thus concerns only the reliability of TraX’s general technique for mapping an antenna’s coverage area.
So both sides agreed that TraX does not suffer from the defects that have plagued other techniques: its maps do not “overpromise[]” their “precision” by excluding plausible areas where the phone might have been located
The district court reasonably applied these guideposts to TraX’s antenna-coverage mapping.
Two final data points support our conclusion that TraX’s antenna-coverage maps adhere to an accepted approach.
Regarding peer review
For starters, the court conceded that nobody has engaged in any peer review of TraX’s amoeba-shaped coverage areas or its algorithm for determining their sizes. See Reynolds, 2021 WL 3750156, at *3. In other words, no scientists have opined on TraX’s validity (one way or the other) in scientific publications. See Gissantaner, 990 F.3d at 464. But, as the Supreme Court has noted, it is sometimes not surprising that peers have not reviewed a given technique if the relevant issue has never “interested any scientist.” Kumho Tire, 526 U.S. at 151. And, as another court has noted, TraX might have few (if any) uses outside of “criminal investigations” to make it worthy of a scientist’s time. United States v. White, 2023 WL 3161953, at *4 (M.D. Pa. Apr. 27, 2023)
In other words, the company predicted “with a 95 percent accuracy that” a cellphone would have been inside the amoeba-shaped area on a TraX map when it connected to the corresponding antenna. Id., PageID 811, 847. True, Ray testified about internal (not external) tests to estimate this error rate. But he explained how his company conducted them, and the district court identified no “serious deficiencies” in his methodology. Bonds, 12 F.3d at 560; see Reynolds, 2021 WL 3750156, at *4.Dr. Jovanovic, by contrast, asked and answered the coverage-accuracy question. Looking at this issue from the perspective of a cellphone provider trying to map its network, he testified that TraX’s coverage areas were nearly universally wrong. Jovanovic Tr., R.125, PageID 1234–38. He thus disagreed with Ray’s 95% accuracy rate—but for an entirely different question that was “immaterial to the Daubert” inquiry. Mitchell, 365 F.3d at 239. Whether a wedge-shaped map or an amoeba-shaped map better displaysan antenna’s real-world coverage area is beside the point to whether a phone would likely fall within the amoeba-shaped area. In fact, Dr. Jovanovic conceded as much. He noted that the coverage “accuracy” question “in terms of mapping” is a “substantial[ly] different” question than “the probability that [a] phone would be in the area indicated” by TraX’s maps. Jovanovic Tr., R.125, PageID 1235. He added that one could “achieve a hundred percent accuracy” for the latter question by drawing big enough coverage areas. Id., PageID 1307. But he never opined on this location-accuracy question for TraX’s maps. So the district court reasonably credited Ray’s low error rate because it stood alone.
To reiterate, we reach a narrow holding. This case’s record indicates that TraX’s antenna-coverage maps adhered to the methods that courts have permitted. Both sides agreed that TraX mapped an antenna’s coverage area (and so a phone’s general location) more broadly than the actual coverage area. And undisputed testimony showed that this conservative choice resulted in a low error rate on the relevant question that the government sought to answer: whether a phone that connected to the antenna would fall within TraX’s coverage area. On this record, the district court did not abuse its discretion in permitting Detective Heikkila to opine about these maps.
Daubert starts at page 17
I noticed a lot of US v Reynolds cases. If there is a different US v Reynolds, please share.
