On December4, 2024, the shocking assassination of UnitedHealthcare CEO Brian Thompson in Midtown Manhattan stunned the nation. The suspect, Luigi Mangione, a 26-year-old from a prominent Maryland family, stands accused of the murder which occurred on a Manhattan sidewalk outside a hotel hosting a business conference. Investigators believe that Mangione's actions were ideologically motivated, aiming to incite opposition to the U.S. health insurance industry through violence. They believe that Mangione meticulously planned the murder, laying in wait with a homemade firearm, and that he orchestrated a calculated escape, before being arrested days later in Pennsylvania,
According to reports, the murder weapon was a 3D-printed ghost gun equipped with a silencer, untraceable due to its lack of a serial number. Police found a similar firearm and silencer in Mangione's backpack at the time of his arrest, both consistent with the weapon used in the murder. Ballistics matched the gun to three spent 9mm shell casings found at the scene.
Escape and Capture
After the shooting, Mangione fled the scene on an electric bike, rode into Central Park, ditched the bike, and hailed a taxi to a bus terminal. He then boarded a bus out of the city.
Five days later, Mangione was arrested at a McDonald's in Altoona, Pennsylvania, after a customer recognized him from surveillance photos and alerted authorities. He was found with a ghost gun, multiple fake IDs, and a handwritten manifesto expressing disdain for corporate America.
Motive: A Manifesto Against Corporate America
Investigators discovered a three-page handwritten document in Mangione's possession that shed light on his motive. The manifesto expressed frustration with the U.S. healthcare system and corporate America, stating such things as that these parasites had it coming and that it had to be done.
Mangione's writings and actions suggest he was inspired by anti-corporate sentiments and possibly influenced by the Unabomber's ideology. His fixation on the healthcare industry and its executives appears to have driven him to commit the targeted killing
What Was Written on the Shell Casings?
Notably, the shell casings had words like "delay," "deny," and "depose" etched onto them, referencing tactics critics say insurance companies use to reject claims. This detail suggests a symbolic motive behind the killing.
What are the Federal Charges Against Him?
On April 25, 2025, Luigi Mangione was arraigned in the U.S. District Court in Manhattan, where he pleaded not guilty to a four-count federal indictment. The charges are as follows:
- Murder Through the Use of a Firearm in Furtherance of a Crime of Violence - This charge alleges that Mangione intentionally used a firearm to commit murder during a violent crime. If convicted, this charge carries the death penalty as a potential penalty. Federal prosecutors filed a notice of intent to pursue the death penalty, citing the ideological motivation behind the crime and its impact on the victim's family and the broader community.
- Firearms Offense - This charge pertains to the illegal possession and use of a firearm during the commission of a violent crime.
- Two Counts of Stalking - These charges allege that Mangione engaged in a pattern of behavior intended to harass, intimidate, or cause fear in Brian Thompson. The stalking charges suggest a premeditated effort to target the victim.
The federal indictment portrays the killing as aimed at protesting the health-care industry. Prosecutors allege that Mangione sought to amplify his message by targeting a prominent figure in the industry.
What are the State Charges Against Him?
In addition to federal charges, Mangione faces separate charges in New York State. He has been indicted on 11 counts, including:
- First-Degree Murder in Furtherance of Terrorism - This charge alleges that the murder was committed with the intent to intimidate or coerce a civilian population or influence government policy through intimidation or coercion. If convicted, Mangione faces a maximum penalty of life in prison without parole.
- Other Related Charges - Involving the planning and execution of the crime.
Mangione has pleaded not guilty to all state charges. His defense team has expressed concerns about the potential impact of the federal death penalty case on the state proceedings.
Ongoing Legal Proceedings
His next federal court hearing is scheduled for December 5, 2025, marking the one-year anniversary of Thompson's death
The case continues to develop as authorities gather more evidence and prepare for trial. Mangione's actions have sparked discussions about the accessibility of ghost guns and the influence of extremist ideologies on individuals.
What Is a Ghost Gun?
In recent years, the term “ghost gun” has become a growing part of conversations about gun control, firearm regulation, and public safety in the United States. But what exactly is a ghost gun, and why has it sparked so much concern among lawmakers, law enforcement, and the public?
A ghost gun is a firearm that is privately made — often assembled by an individual — without serial numbers or any official markings that would make it traceable by authorities. Unlike traditional guns sold by licensed dealers, ghost guns do not go through regulated sales channels and are not registered. If a ghost gun is used in a crime, investigators usually cannot trace it back to its maker or owner through standard methods. As a result, they are essentially invisible to law enforcement tracking systems.
Where Does Someone Get a Ghost Gun?
A ghost gun might be:
- Assembled from "buy-build-shoot" kits that include nearly all the parts needed to build a gun at home.
- Created using unfinished receivers (also called 80% receivers or 80% lowers), which are sold legally because they are not classified as functioning firearms under federal law — until the final steps of fabrication are completed by the purchaser. With basic tools (like a drill press or simple hand tools), the unfinished receiver is completed. Some companies sell easy-to-use jigs and instructions to simplify the process.
- Produced using advanced technology such as 3D printing, allowing individuals to manufacture nearly all parts without purchasing through traditional vendors. Once completed, the frame or receiver can be fitted with other parts — such as barrels, slides, triggers, and magazines — to create a fully functional firearm.
Because they lack serial numbers and typically bypass background checks, ghost guns are particularly attractive to individuals prohibited from owning firearms — including felons, domestic abusers, or minors.
Why Are Ghost Guns Controversial?
Ghost guns have become a major point of concern for several reasons:
1. No Background Checks
Because ghost guns can be acquired without going through a licensed dealer, people who would normally be denied the ability to buy a gun — like those with felony convictions or mental health prohibitions — can still build one.
2. Untraceability
When a conventional gun is used in a crime, law enforcement can trace its history through serial numbers and registration records. With ghost guns, that forensic avenue is cut off, making investigations much harder.
3. Rising Usage in Crime
According to reports from agencies like the ATF (Bureau of Alcohol, Tobacco, Firearms and Explosives), ghost guns have been turning up more frequently at crime scenes nationwide. In some cities, they account for a significant percentage of weapons seized by police.
4. Easy Access for Minors
Because ghost gun kits can be purchased online without background checks and without strict age verification, minors can potentially obtain or build firearms without adult supervision.
What Laws Exist About These Guns?
The regulation of ghost guns is a developing area of law:
- Federal Level: In 2022, the Biden Administration finalized a rule that redefines "frame or receiver" to close the so-called "ghost gun loophole." The rule requires that kits and incomplete receivers be treated as firearms under the law, meaning they must have serial numbers, and sellers must run background checks.
- State Level: Several states, including California, New Jersey, and New York, have passed stricter laws regulating or banning ghost guns outright. These laws often require private manufacturers to serialize home-built firearms and impose registration requirements.
- Legal Challenges: Ghost gun regulations are facing active challenges in courts. Some argue that strict regulations infringe upon Second Amendment rights, while others emphasize the public safety concerns that justify tighter control.
Illinois Ghost Gun Laws Lead the Way
Illinois has taken a firm stance against "ghost guns"— untraceable, privately assembled firearms that lack serial numbers and often bypass background checks. These weapons, frequently constructed from kits or 3D-printed components, have become a growing concern for law enforcement due to their use in criminal activities and their appeal to individuals prohibited from owning firearms.
The Legislative Response: HB4383
In May 2022, Governor JB Pritzker signed House Bill 4383 into law, making Illinois one of the first Midwestern states to ban ghost guns statewide. The legislation prohibits the sale, possession, and manufacture of unserialized firearms and firearm parts. It also requires that any existing homemade guns be serialized by a licensed federal firearms dealer. The law became fully effective on November 14, 2022, with specific provisions targeting 3D-printed firearms taking effect in June 2022.
Enforcement and Impact
The Illinois State Police have actively enforced the new regulations. For instance, in May 2022 alone, they investigated 28 cases involving ghost guns. These untraceable weapons have been linked to various crimes, including armed carjackings and incidents involving minors bringing loaded ghost guns to schools.
In Cook County, the State's Attorney's Office has prioritized cases involving ghost guns, treating them as detainable felony offenses. This approach underscores the seriousness with which local authorities view the threat posed by these weapons.
Federal Alignment and Legal Challenges
Illinois' actions align with federal efforts to regulate ghost guns. In 2022, ATF created a rule requiring serialization and background checks for kits and parts. This rule was upheld by the U.S. Supreme Court in March 2025, reinforcing the legal foundation for Illinois' measures.
Attorney General Kwame Raoul has been a vocal advocate for these regulations, emphasizing that ghost guns enable individuals who are legally prohibited from owning firearms to circumvent safety measures. He has urged the U.S. Supreme Court to uphold federal ghost gun regulations, highlighting their importance in preventing gun violence and aiding law enforcement.
Illinois' Comprehensive Approach
Illinois’ approach reflects a commitment to public safety and a proactive stance against emerging threats in firearm technology. By enforcing serialization requirements and aligning with federal regulations, the state aims to curb the proliferation of untraceable firearms and reduce their use in criminal activities.
As legal challenges continue and technology evolves, Illinois' policies may serve as a model for other states grappling with the complexities of regulating ghost guns.
Are Ghost Guns Always Illegal?
No, ghost guns are not inherently illegal under federal law — provided the individual building them is legally allowed to own a firearm and the gun is not intended for resale. However, if a prohibited person builds a gun, or if someone manufactures and sells guns without a federal firearms license (FFL), then serious criminal penalties can apply.
Some states, however, have criminalized possession, manufacture, or transfer of unserialized guns, regardless of intent.
The Future of Ghost Guns
As technology advances and 3D printing becomes even more accessible, the ability to privately manufacture guns will likely continue to grow. Policymakers are struggling to strike a balance between respecting constitutional rights and addressing the very real public safety challenges posed by untraceable firearms.
Expect more legal battles, evolving regulations, and political debates in the coming years over the best way to regulate — or not regulate — ghost guns.
Conclusion
The assassination of Brian Thompson underscores the potential dangers posed by individuals radicalized by anti-corporate ideologies. Mangione's meticulous planning, use of untraceable weapons, and symbolic messages highlight the complexities law enforcement faces in preventing such targeted attacks. As the legal process unfolds, the case serves as a stark reminder of the intersection between personal grievances and acts of violence. Mitchell S. Sexner & Associates LLC represents client in both criminal and injury law and can be reached at (312) 644-0444.