Luigi Mangione appears for a pre-trial hearing at Manhattan Criminal Court in New York, Wednesday, June 17, 2026. (AP Photo/Angelina Katsanis, Pool) (NewsNation) — Luigi Mangione’s “manifesto,” found in a notebook after his capture, could play a role in his defense team’s strategy to claim he was having a severe emotional episode when he allegedly shot and killed UnitedHealthcare CEO Brian Thompson in 2024.
Mangione’s legal counsel is expected to pivot his defense strategy to claim he was enduring an episode of severe emotional distress for his killing in New York City in 2024.
NBC News Legal Analyst Danny Cevallos told NewsNation that Mangione’s defense team is utilizing “affirmative defense” in an attempt to downgrade murder charges.
“‘Extreme emotional disturbance’ is neither an insanity defense nor a path to acquittal. It is something called an affirmative defense. If proven, it does not erase liability for an intentional killing but downgrades murder in the second degree to first-degree manslaughter. It is mitigation, not acquittal.” Cevallos said.
What does Luigi Mangione’s ‘manifesto’ say?
After Luigi Mangione’s arrest, information from his notebook was released, detailing that he allegedly wished to kill Thompson in order to “prove a political point about the health insurance industry” and “extract human life force for money.”
“So, say you want to rebel against the deadly, greed-fueled health insurance cartel,” an entry from the notebook reads. “Do you bomb the HQ? No. Bombs=terrorism,” the alleged Mangione manifesto read.
The notebook also acknowledged previous plans for a bombing in an effort to generate headlines.
Mangione reported back pain, brain fog on social media posts
Additionally, Mangione underwent a difficult spinal surgery prior to Thompson’s murder.
He repeatedly posted on the social media site Reddit about his recovery, telling users to push back on doctors who advise simply managing the pain.
Mangione also posted that he had severe brain fog and had trouble sleeping, saying his school grades were suffering because of it.
How effective can an extreme emotional disturbance defense be?
Cevallos detailed that using the language of an extreme emotional disturbance as a defense is a hard one to win, but it is a strategy to try to elicit understanding for why an individual like Mangione may have intentionally killed someone.
“The defendant still stands convicted of an intentional homicide, just a lesser-graded one,” Cevallos said.
He adds the defendant must prove that he suffered that extreme emotional disturbance, leading to a loss of self-control or a “reasonable explanation or excuse for the disturbance.”
“The idea behind extreme emotional disturbance as a defense is that some intentional homicides are ‘an understandable human response deserving of mercy,’” Cevallos said, adding a jury must find the reaction reasonable, not just factual.
Unsealed Luigi Mangione records could affect federal trial
Defense attorney Karen Agnifilo argued that unsealing those records was highly prejudicial to Mangione’s federal case, where such a defense is not legally possible.
Prosecutors argued Thompson’s family has a right to know what happened leading up to his death, adding that his 78-year-old grandmother has waited 18 months to see the case move forward.
The judge ordered the defense to release the information by Thursday.
Psychiatric defense a strategy to seek lesser charges: Attorney
Chicago-based attorney Tamara Holder agreed with Cevallos that the psychiatric defense is most often a legal tactic to lessen charges or sentencing for a crime.
“We don’t know the specifics of his psychiatric defense just yet, but it could be PTSD, child abuse, etc.,” Holder said. “Interestingly, early on, there was a lot of talk about his unsuccessful surgeries and chronic pain. Maybe that led to depression and PTSD. It will be interesting to see what’s next.”
Manifesto could corroborate defense’s claim of extreme emotional distress
Forensic psychology researcher Alexandra (AJ) Greer, who studies psychopathy and violent crime, said the manifesto could be used as evidence to corroborate the defense’s claim that he was unable to make a clear-minded decision.
“The manifesto could be used to support a psychiatric defense if there’s clear evidence of disorganized thinking, delusional beliefs, or some sort of thought disorder,” Greer said. “Theoretically, it could be used to support the existence of other mental health disorders, but I’d expect the defense would need to rely on previous case law and a lot of additional information to go forward with that.”
Luigi Mangione will avoid death penalty
A judge ruled earlier this year that Mangione would not face the death penalty, despite the Trump administration’s bid to have him executed for what it called a “premeditated, cold-blooded assassination that shocked America.”
A federal judge dismissed the federal murder charge, arguing it was technically flawed, doing so to “foreclose the death penalty as an available punishment to be considered by the jury,” as it weighs whether to convict Mangione.
Mangione is facing state charges that carry a sentence of up to life in prison. Additional federal charges allege he stalked Thompson. He has pleaded not guilty in both cases.
Diana Falzone is the senior national investigations reporter at NewsNation Digital, covering the federal government, warzones and top-level criminal investigations.
Add as preferred source on Google Tags Brian ThompsonCopyright 2026 Nexstar Media Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
Link copiedMore Court Battles News
See All
Administration DOJ uses alleged UFC plot to argue for Trump ballroom by Sophie Brams 15 hours ago Administration / 15 hours ago 
