Utah Court of Appeals Hears Challenge to Reliability of ‘Torrential Downpour’ in Gaines Case

SALT LAKE CITY — A three‑judge panel of the Utah Court of Appeals on Monday heard competing arguments over whether evidence derived from a law‑enforcement software tool called Torrential Downpour should have been admitted at trial in State v. Gaines and whether any error was harmless.

At the start of oral argument, Judge Ryan Tenney explained procedure and time limits, then invited counsel to proceed. Rachel Foles, representing appellant Jeremy “Jim” Gaines, told the court that Gaines’s brief raises three principal issues and two additional Rule 23(b) claims and argued that “the district court abused discretion in denying Jim’s motions regarding Torrential Downpour and seeking additional discovery,” framing the centerpiece issue as the tool’s reliability under Rule 702.

The state, represented by Marion Decker, urged the panel to affirm, saying the record supports an alternative Rule 702 showing of general acceptance and stressing investigators’ surrounding circumstances: encryption on several devices prevented direct image verification and Gaines made admissions to downloading a known collection. Decker said the task‑force officers’ long experience using Torrential Downpour — described in the record as a combined ‘‘hundreds’’ of uses and Sergeant Jones’s 30–40 uses — along with the defendant’s statements, supported admissibility.

The panel’s questioning focused on two linked questions: (1) whether the trial court’s motion sufficiently preserved a broad challenge to Torrential Downpour’s reliability or instead targeted individual testimony, and (2) whether the record supplied the kind of proof Rule 702 requires before opinion‑style evidence about the tool goes to the jury. Judge Tenney asked whether an officer’s “lived experience” — testifying that the program reliably led investigators to images in a high percentage of uses — could satisfy the threshold, while other panelists explored whether general‑acceptance proof or peer‑reviewed studies would be required for reliability when a tool’s inner workings are not disclosed outside law enforcement.

Foles answered that operator testimony is not the same as expert explanation of the software’s linking and hashing methods; she argued the record lacks external validation or peer‑reviewed evidence because Torrential Downpour is law‑enforcement‑only. Decker countered that encryption on the devices prevented confirmation of images and that Gaines’s admissions about a known collection (the MOSHKA/Moshka file) — described in the record as a file with seven recognized images — undercut any claim of prejudice from admitting the Torrential Downpour evidence.

The judges also examined harmless‑error scenarios. Several panelists pressed whether a hypothetical retrial without the Torrential Downpour evidence would leave sufficient proof to sustain the counts at issue. The State suggested that Gaines’s admissions to downloading the MOSHKA collection and the investigative context could sustain at least the counts tied to that file; the defense maintained that without a direct link between the IP addresses and images, reasonable doubt about intent or knowing possession could remain.

No ruling was issued from the bench. Judge Tenney closed the argument by saying the court would “do our best to issue a decision as soon as we can.”

The appeal centers on evidentiary thresholds under Rule 702 and on how courts should treat law‑enforcement‑only forensic tools that are not publicly documented. The court’s forthcoming written opinion will resolve whether the trial court’s admission of Torrential Downpour evidence was an abuse of discretion and, if so, whether the error was harmless in light of Gaines’s statements and the other investigative evidence.

Next steps: the panel said it will issue a decision in due course; no further arguments in this matter were scheduled and the session was adjourned.