In a closely watched legal battle unfolding in New York, Judge Gregory Carro has handed down a pivotal ruling that will shape the upcoming murder trial of Luigi Mangione, the man accused of killing UnitedHealthcare CEO Brian Thompson in December 2024. The decision, issued on May 18, 2026, determines precisely which pieces of evidence prosecutors may present to the jury—a choice that could influence the outcome of one of the most high-profile corporate crime cases in recent memory.
The heart of the controversy centers on a gun and a notebook, both found in Mangione’s possession after his arrest at a McDonald’s in Altoona, Pennsylvania, five days after the shocking murder. According to The Associated Press, Judge Carro ruled that these items can be used as evidence at Mangione’s trial, rejecting the defense’s claim that they were seized illegally. The judge’s ruling is a significant win for prosecutors, who have argued that the gun—a 3D-printed pistol—and the notebook, which allegedly contains plans to "wack" a health insurance executive, directly tie Mangione to the crime and shed light on his possible motive.
But not everything seized that day will make it before the jury. The judge also excluded several items officers initially found in Mangione’s backpack at the McDonald’s, including a loaded gun magazine, cellphone, passport, wallet, and computer chip. As reported by Fox News, Carro determined that this initial search amounted to an "improper warrantless search" under New York law. He explained that once police had moved the backpack outside Mangione’s "grabbable area," they had no immediate justification to continue searching it without a warrant, especially as other restaurant customers were present and the situation was under control.
However, the story takes a turn at the police station. There, officers conducted what Carro described as a valid inventory search—a routine process where police catalog the belongings of an arrestee. During this search, they discovered the 3D-printed pistol and the notebook, both of which are now admissible in court. This distinction, as detailed in The Guardian, highlights the complex interplay between law enforcement procedures and the legal protections afforded by the U.S. Constitution against unreasonable searches and seizures.
Carro’s decision follows a nine-day suppression hearing, where Mangione’s defense team vigorously argued that all evidence from the backpack should be excluded, insisting that the search was unlawful because it was conducted before a warrant was obtained. Prosecutors, on the other hand, maintained that Altoona police procedures justified the initial search for dangerous items. Yet, as the judge noted, New York law ultimately governs what evidence is admissible in the state trial, and the prosecution had not met its burden to prove exigency—a legal term for an emergency situation that would allow a warrantless search.
The ruling is not just a procedural footnote; it strikes at the core of the prosecution’s case. The notebook, prosecutors allege, contains Mangione’s handwritten diary entries, including praise for notorious Unabomber Ted Kaczynski and musings about rebelling against what he called "the deadly, greed fueled health insurance cartel." According to court filings cited by The Associated Press, the notebook also outlines apparent to-do lists and getaway plans, potentially revealing Mangione’s state of mind and intent. In a particularly chilling detail, police found ammunition marked with the words "delay," "deny," and "depose"—terms that echo language used to describe insurance industry practices of avoiding claim payments.
The gun, meanwhile, is a 3D-printed 9mm pistol that prosecutors say matches the weapon used to shoot Thompson from behind as he walked to UnitedHealth Group’s annual investor conference in Manhattan on December 4, 2024. Surveillance video reportedly shows a masked gunman approaching and firing on Thompson in a brazen attack that stunned both the business world and the city at large.
Mangione, 28, was arrested on December 9, 2024, after a customer at the Altoona McDonald’s recognized him from police photos released during a nationwide manhunt. When officers approached, Mangione initially identified himself as "Mark Rosario" and handed over a New Jersey driver’s license with that name—an alias investigators later linked to bus tickets and hostel stays in New York, as testified by an NYPD lieutenant. The arrest scene was tense, with more than eight officers converging on Mangione before he was officially taken into custody and read his Miranda rights.
Judge Carro’s ruling also touched on statements Mangione made to police before being Mirandized. The defense argued that these statements—including Mangione’s admission to providing a fake name—should be excluded, as he was effectively in custody and had not been informed of his rights. Carro agreed in part, ruling that some of Mangione’s pre-Miranda statements would be inadmissible, especially those made in response to police interrogation or its functional equivalent. This nuanced approach gives both sides something to claim as a partial victory.
Mangione has pleaded not guilty to all charges, both in state court—where he faces nine counts, including second-degree murder—and in federal court, where he is charged with stalking and other crimes. The top two state charges, first-degree murder and second-degree murder as terrorism crimes, were previously dismissed by Carro in September 2025, but the remaining counts still carry the possibility of a life sentence if Mangione is convicted. The state murder trial is set to begin on September 8, 2026, with the federal trial, involving stalking charges, scheduled for October 13, 2026. Jury selection for the federal case is expected to start in mid-October, with opening statements and testimony likely to follow in early November.
In the courtroom, the gravity of the proceedings was palpable. About two dozen Mangione supporters, some donning "Free Luigi" T-shirts, crowded the gallery as Carro summarized his decision. Mangione himself, dressed in a navy blue suit, remained silent, occasionally craning his neck to catch the exchanges among attorneys at the bench. The hearing, which lasted only about 15 minutes, marked the latest chapter in a legal saga that has gripped the city and drawn national attention.
The defense has signaled it will continue to challenge the admissibility of evidence and the conduct of law enforcement, while prosecutors are preparing to present what they believe is a compelling case built on the gun, the notebook, and the circumstances of Mangione’s arrest. As the September trial date approaches, both sides are bracing for a courtroom battle that will test the boundaries of criminal procedure and the power of forensic evidence in the digital age.
With the judge’s ruling now in place, the stage is set for a dramatic trial where every piece of evidence—and every legal argument—will be scrutinized under the spotlight. The outcome could have far-reaching implications, not only for Mangione and the family of Brian Thompson, but also for how courts navigate the delicate balance between public safety and constitutional rights in high-stakes criminal cases.