Artificial intelligence mode
John D. Gartner is a psychologist and former part-time assistant professor at Johns Hopkins University Medical School who has frequently commented on Donald Trump’s mental health. As of early 2026, he remains a prominent critic, claiming that President Trump is exhibiting signs of accelerating cognitive decline and malignant narcissism.
Key Assessments & Activism
*Malignant Narcissism: Gartner describes Trump as a "malignant narcissist," a severe personality disorder characterized by narcissism, psychopathy, paranoia, and sadism.
*Dementia Claims: Since 2024, Gartner has argued that Trump shows "gross signs of dementia" rather than normal aging. He cites specific speech patterns, such as phonemic paraphasia (starting a word but finishing it with nonsense sounds), as clinical evidence.
*"Duty to Warn": Gartner founded the organization Duty to Warn, which argues that mental health professionals have an ethical obligation to alert the public when a leader's mental state poses a danger to the nation.
*"Shrinking Trump" Podcast: Along with psychologist Harry Segal, Gartner co-hosted this podcast for 70 episodes to analyze Trump’s psyche. The series concluded in October 2025, though Gartner continues to give interviews on the subject.
Publications
Gartner has authored and contributed to several books focused on these assessments:
*The Dangerous Case of Donald Trump: A collection of essays by 27 mental health experts (2017).
*Rocket Man: Nuclear Madness and the Mind of Donald Trump.
Controversy
Gartner’s work is controversial within the medical community because it often bypasses the Goldwater Rule, an ethical principle that discourages psychiatrists from diagnosing public figures they have not personally examined. Critics, such as psychiatrist Allen Frances, argue that labeling Trump as "mentally ill" can stigmatize the illness and that his fitness should be addressed through political activism rather than psychology.