In a pivotal pretrial motion, Donald Day Jr., a 60-year-old Arizona man, seeks to exclude evidence related to a high-profile shooting in Australia, arguing its introduction would be prejudicial and irrelevant to his case. Mr. Day, facing federal charges related to online threats and firearms violations, contends that government prosecutors aim to establish “guilt by association” by linking him to an incident he had no involvement in—the December 12, 2022, Wieambilla shooting in Queensland, Australia.
The Wieambilla shooting involved three individuals—Gareth, Nathaniel, and Stacey Train—who killed two police officers and a bystander before being shot by law enforcement. While Mr. Day had interacted with the Trains online, he never met them in person and had no knowledge of their plans. Despite this, according to this latest motion, authorities in both Australia and the United States scrutinized him for nearly a year, attempting to establish a connection. Ultimately, no charges related to the shooting were brought against him. However, the U.S. government has indicted him based on a video he posted four days later, in which he made statements about self-defense and resisting government oppression. Prosecutors argue that these statements constitute threats against law enforcement.
Mr. Day’s motion argues that the introduction of evidence related to the Wieambilla shooting would violate his First and Fifth Amendment rights. He asserts that the government’s attempt to tie him to the Trains is constitutionally impermissible, as “guilt by association” cannot serve as a basis for criminal liability. Furthermore, he contends that allowing such evidence would mislead the jury, create unfair prejudice, and waste time by forcing the defense to address a foreign incident rather than focusing on the actual charges.
To mitigate these risks while still allowing the government to present necessary context, Mr. Day proposes limiting the discussion of the Wieambilla shooting to a concise, stipulated statement of facts. Here is what is proposed:
This would establish that he had online interactions with the Trains, that they posted a video mentioning him on the day of the shooting, and that he later posted his own video. The defense further requests that only one government witness be allowed to present this limited context, preventing an undue emphasis on the Australian incident.
A number of exhibits were attached to the motion. Below is a summary of their contents.
Senior Constable Costello Statement: Senior Constable Costello provides details regarding the online interactions between Donald Day Jr. and the Trains (Gareth, Nathaniel, and Stacey). His statement outlines the digital footprint left by Mr. Day, emphasizing YouTube videos, comments, and other communications. Costello’s testimony appears to establish a connection—albeit indirect—between Mr. Day and the ideology of the Trains leading up to the Wieambilla shooting.
Detective Sergeant Gibb Statement: Detective Sergeant Gibb focuses on the forensic analysis of electronic devices and online interactions. His testimony highlights the government’s investigation into extremist rhetoric and whether Mr. Day’s online statements reflected alignment with, or encouragement of, the Trains’ actions. Gibb also provides insights into metadata analysis and the timeline of Mr. Day’s communications before and after the Wieambilla shooting.
Senior Sergeant Gleeson Statement: This statement describes the law enforcement response to the Wieambilla shooting, the intelligence gathered about the Trains before and after the attack, and how authorities investigated their digital footprint.
Detective Acting Sergeant Hindmarsh Statement: Detective Acting Sergeant Hindmarsh details some of the images he captured as part of the investigation.
Detective Sergeant Karpiel Statement: Detective Sergeant Karpiel provides testimony on how law enforcement connected Mr. Day to the Trains through online activity. He discusses the legal distinction between First Amendment-protected speech and criminal threats, arguing that Mr. Day’s video posted after the Wieambilla shooting contained language that could be interpreted as incitement or intimidation. Karpiel’s statement also includes an assessment of how law enforcement evaluated Mr. Day’s social media posts for potential threats
Detective Senior Constable Neems Statement: Detective Senior Constable Neems details some of the phone evidence as part of the case.
Detective Senior Sergeant Partridge Statement: Detective Partridge provides insight into the tactical response to the Wieambilla shooting.
Detective Inspector Pollard Statement: Detective Inspector Pollard examines telecommunication forensic extractions.
Citation: Citation: United States v. Day, No. CR-23-8132-PCT-JJT (D. Ariz. Mar. 5, 2025) (Motion in Limine).