Case Explained: THOMPSON V. RIVERSIDE COUNTY SHERIFF’S DEPARTMENT, ET AL.

Court: United States Court of Appeals for the Ninth Circuit Filed: 2026-06-17 Docket: 5:19-cv-00122-AB-SHK The Ninth Circuit affirmed the district court’s grant of summary judgment in favor of the Riverside County Sheriff’s Department and its officers in a civil rights action brought under 42 U.S.C. § 1983 alleging violations of the First and Fourth Amendments. The court held that Thompson’s claims for unlawful arrest and retaliatory arrest necessarily failed because Deputy Moon had probable cause to arrest her. Under Ninth Circuit precedent, the existence of probable cause defeats both Fourth Amendment unlawful arrest claims and First Amendment retaliatory arrest claims. The record established that Thompson willfully resisted, delayed, and obstructed a peace officer by refusing multiple orders to clear a security screening area while yelling loudly, satisfying the elements of California Penal Code § 148(a)(1). Regarding procedural issues, the court reviewed the district court’s denial of a motion to compel additional discovery for abuse of discretion. It found no error in the lower court’s refusal to order production of missing surveillance footage, noting Thompson provided no evidence that defendants tampered with the video and that defendants had supplied all footage in their possession. Additionally, the court affirmed the district court’s evidentiary ruling authenticating the surveillance video, concluding that Deputy Moon’s declaration sufficiently verified the video depicted the incident under Federal Rule of Evidence 901(b). The practical consequence is that the judgment for the defendants stands, and Thompson’s lawsuit is dismissed with no further relief available on these claims. Do It For The Case Law is a news reporting service. Nothing in this episode constitutes legal advice.