Luigi Mangione, a 27-year-old man accused of murdering UnitedHealthcare CEO Brian Thompson, allegedly documented his plans to kill the executive in a diary, according to a recent court filing by state prosecutors. The diary entries, found in a red notebook, were submitted as evidence in a New York court on Wednesday.

Prosecutors claim that Mangione wrote about his intentions months before Thompson was shot dead in December 2022. The notebook was seized during Mangione's arrest in Pennsylvania after a five-day manhunt for the suspected killer.

In one entry dated August 2024, Mangione reportedly expressed his disdain for the healthcare industry, stating, "So say you want to rebel against the deadly, greed fueled health insurance cartel. Do you bomb the HQ? No. Bombs=terrorism." This entry suggests a belief that violent actions against the industry would be unjustified.

Instead of a bombing, Mangione allegedly proposed a more targeted approach in an entry from October, suggesting that someone should "wack [sic] the CEO at the annual parasitic bean-counter convention." He elaborated, saying, "It's targeted, precise, and doesn't risk innocents. Most importantly, the point is self-evident." He envisioned the act making headlines, stating, "Insurance CEO killed at annual investors conference."

The court filing aims to support the terrorism enhancement added to Mangione's first-degree murder charge. Manhattan Assistant District Attorney Joel Seidemann emphasized the strength of the evidence against Mangione, stating, "If ever there were an open and shut case pointing to defendant’s guilty, this case is that case." He described Thompson and UnitedHealthcare as symbols of what Mangione viewed as a "deadly greed-fueled cartel."

Thompson, 50, was fatally shot outside the New York Hilton hotel just hours before he was scheduled to speak at an investor conference. The shooter, who wore a mask, fled the scene on a bicycle and managed to evade capture. Five days later, a McDonald's employee in Altoona, Pennsylvania, recognized Mangione from police images and alerted authorities.

The murder of Thompson sparked national discussions about the high costs of healthcare in the United States. Mangione's hearings in New York City have drawn protests against the healthcare industry, with supporters gathering outside the courthouse calling for his release.

As the legal proceedings continue, Mangione's defense fund has exceeded $1 million, following a directive from Attorney General Pam Bondi for federal prosecutors to pursue the death penalty. Mangione is scheduled to appear in court for his state charges on June 26.