Washington, D.C.: Matt Lambert, a wealthy emergency room physician, has been identified as the gunman behind a deadly shooting at a Washington, D.C., apartment building gym. The incident reportedly followed a prolonged dispute over alleged black mold contamination in his luxury penthouse.
Lambert had reportedly been fighting with the management of the Metropole Condominium Association over moisture, water damage and suspected mold problems inside his approximately $1.1 million property. He had publicly discussed the complaints through social media posts.
According to The Times of India, Lambert filed a lawsuit against the condominium association last year, alleging that exterior building repairs and scaffolding contributed to mold spreading inside his apartment. The dispute reportedly involved significant damage and ongoing maintenance complaints.
Shortly before the shooting, an X account reportedly linked to Lambert posted a message stating, “My manifesto is an engineering report.” The account, identified as @OfMiceandMold, contained numerous posts about suspected mold growth and problems inside his residence.
Lambert reportedly lived in a seventh-floor penthouse at 1515 15th Street NW in Washington’s Logan Circle neighborhood. He had purchased the property for approximately $1.095 million, according to information cited in reports about the incident.
The shooting occurred inside the ground-floor gym of the residential building. Lambert reportedly opened fire, killing building manager James Stuart, 46, before returning to his apartment, where he later died from a self-inflicted gunshot wound.
Authorities also reported that several other people were wounded during the incident. Investigators said the ongoing disagreement involving Lambert and the building’s homeowners association appeared connected to the attack, although the investigation continued.
Lambert described himself professionally as a board-certified emergency physician with more than two decades of clinical experience. His personal website also identified him as a healthcare technology executive, published author, musician and philanthropist.
The Matt Lambert case also drew attention because of his repeated public complaints about suspected black mold. His social media activity prompted wider online discussions about the alleged apartment conditions and the circumstances surrounding the shooting.
