A former FBI supervisory special agent said writings found on ammunition recovered after the fatal shooting of conservative activist Charlie Kirk may provide critical leads and help investigators determine whether the attack was driven by grievance, ideology or both.
Charlie Kirk, founder and CEO of Turning Point USA, was fatally shot during a rally at Utah Valley University on Sept. 10. Authorities have identified a suspect as Tyler Robinson, 22, and announced an arrest about 33 hours after the killing, according to law enforcement and media reports. Investigators have said they recovered unspent cartridges marked with messages; one reportedly read “Catch a fascist,” and officials previously described the markings as referencing transgender and anti-fascist themes.
Jason Pack, who spent 21 years with the FBI and has supervised manhunts including the Boston Marathon bombing investigation, told the Daily Mail that inscriptions on ammunition are more than stray graffiti. "Writings like this are psychological fingerprints," Pack said in an analysis published by the outlet, arguing that such messages can reveal the perpetrator’s intended narrative and motive and help link physical evidence to digital records, journals, social media posts and videos.
Pack compared the Kirk case to the 2023 killing of UnitedHealthcare CEO Brian Thompson, alleging the same pattern of message-bearing shell casings. Investigators in the Thompson case reportedly found three shell casings with the words "Deny," "Defend" and "Depose," which Pack said echoed a corporate-industry mantra — and that writings on ammunition in both cases suggested the attackers intended to send a broader message beyond the act itself.
Law enforcement officials treating the Kirk case have pursued two parallel lines of work: a manhunt to secure the suspect and a forensic investigation to assemble evidence for prosecution. Investigators processed the rally site for shell casings, fingerprints, DNA and surveillance footage while fugitive squads and tactical teams used public tips, license-plate readers and aerial surveillance to locate a person of interest, according to Pack and court filings in related cases.
Pack noted similarities between the suspect in the Kirk case and Luigi Mangione, who was later captured after the slaying of Thompson. Both alleged shooters were young, reportedly dressed in black and appeared to have targeted a single individual. Mangione, 26 at the time of the Thompson killing, was on the run for several days before his arrest after surveillance images led to public recognition; Pack said law enforcement’s deliberate decision to release sharper images in the Kirk case quickly produced tips, and that one of the suspect’s relatives reportedly contacted authorities.
Investigators collecting evidence will attempt to match any inscriptions to other items in the suspect’s life, Pack said, including social media activity, private writings and communications that may show a progression from grievance to action — a pathway law enforcement often identifies in targeted, premeditated attacks. Pack used the term "leakage" to describe instances in which a perpetrator expresses intent publicly or to acquaintances before carrying out violence; officials said finding such pre-attack indicators is a key focus of the ongoing inquiry.
Ballistics analysts will work to match casings to a weapon, and forensic teams said they are cataloging physical traces such as DNA or latent prints that could link the suspect to the crime scene. Surveillance footage from the university and surrounding areas is being reviewed; investigators frequently combine timestamps, witness statements and transactional records to reconstruct a suspect’s movements before and after an attack.
Law enforcement officials have cautioned that while inscriptions and other evidence can suggest motive, corroboration is required to establish legal intent and to support criminal charges. Authorities in the Kirk investigation have not announced formal motive findings, and prosecutors will determine charges and pursue a case based on the totality of physical and digital evidence gathered.
Pack said that in high-profile manhunts the outcome typically involves surrender, tactical capture or a forced confrontation, and he described the quick arrest in the Kirk case as a favorable development for investigators seeking to preserve evidence and build a prosecutable case. He also highlighted the role of the public: tips in recent targeted killings have led to rapid identifications when combined with enhanced surveillance imagery.
Federal and local authorities continue to process the crime scene and examine forensic and digital materials. Officials have urged anyone with information to contact investigators, and they have said the investigation remains active as they prepare evidence to present to prosecutors.
The investigation is unfolding amid heightened scrutiny of political violence and threats to public figures, and authorities said they will move cautiously to verify motives, establish the chain of custody for physical evidence and develop a case that can withstand judicial review. Pack’s analysis underscores how investigators use both physical artifacts and online behavior to trace the arc of a violent act and the narrative a suspect may have intended to convey.