ER Doctor Kills Condo Manager in Gym Ambush Over Mold Feud

WASHINGTON — An emergency room physician who spent years locked in a bitter legal battle over black mold and water damage in his $1.1 million penthouse opened fire Thursday morning inside a popular Logan Circle gym, killing the building manager and wounding four others before barricading himself in his unit and taking his own life.

Police identified the gunman as Dr. Matt Lambert, 55, a board-certified emergency physician and healthcare consultant who lived in Unit 704 of the Metropole condominium at 1515 15th Street NW. The fatal victim was James Stuart, 46, the property manager of the same building. Authorities said Lambert targeted Stuart amid an ongoing dispute with the Metropole Condominium Association and its management company.

The attack unfolded shortly before 8 a.m. on November 12 at Vida Fitness, the ground-floor gym in the Metropole complex, roughly a mile from the White House. Lambert, himself a gym member, entered and shot Stuart at close range with a handgun. Security video and witnesses indicated Stuart was shot in the back or neck while working out, his usual morning routine. One gym-goer recalled hearing a loud bang and seeing a man collapse with blood pooling around him.

Lambert then fled upstairs. From his seventh-floor balcony or patio, he fired a rifle at people on the street below, wounding four others — two men and two women. One remained in critical condition Thursday; the others suffered non-life-threatening injuries. Officers arrived within about 30 seconds of the first 911 calls. Lambert fired at police at least twice during the ensuing standoff. Negotiators spoke with him for more than an hour before hearing a gunshot inside. Officers forced entry and found him dead from a self-inflicted wound. Three firearms — a handgun, a rifle and a shotgun — were recovered, along with containers of gasoline.

Interim Metropolitan Police Chief Jeffery Carroll said the shooting appeared linked to Lambert’s long-running conflict with the condominium association over maintenance issues, including mold. “There has been an ongoing dispute between the suspect in this case and the building, condo, homeowners association management regarding maintenance issues — mold and the like — that there was a civil case that he filed against them. So we believe that it’s related to that,” Carroll told reporters. Ward 2 Councilmember Brooke Pinto said preliminary information indicated Lambert had walked into the gym specifically to target someone with whom he was in active litigation.

Court records show Lambert bought the roughly 1,200-square-foot seventh-floor unit for about $1.095 million in 2016. In March 2025 he sued the Metropole Condominium Association and property manager EJF Real Estate Services, alleging that facade repairs in 2023–2024 allowed water intrusion that produced moisture, mold and more than $100,000 in damages. He claimed the unit became largely uninhabitable, forcing him to live for months without a functioning shower, dryer, HVAC system or cooking facilities. He said he stripped the apartment to the studs at his own expense, discovering extensive black mold, and spent tens of thousands more on independent testing, remediation and legal fees.

An X account linked to Lambert, @miceandmold (also styled OfMiceandMold), chronicled the grievances for months with photos of water stains, scaffolding, humidity readings and alleged rodent issues. Hours before the shooting he posted images of the gutted apartment and wrote about “two years of living in luxury (and the start of 6 months with no shower, dryer, HVAC, and cooking).” Minutes before opening fire he posted: “My manifesto is an engineering report,” attaching a document describing suspected microbial growth and repair estimates.

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In earlier interviews with a reporter who later wrote about the dispute, Lambert described the conflict as “psychological warfare.” He claimed that when he showed Stuart independent mold findings, the manager dismissed the odor as smelling “like cologne” and referred the matter to lawyers. The association denied liability and at one point suggested laundry dryers from the gym below may have contributed to excess moisture. Mediation in the lawsuit had been scheduled for 2027.

Lambert’s professional background included more than two decades of clinical experience, work at major hospitals, healthcare technology roles and philanthropic medical trips. His website described him as a published author and musician who split time between Washington and West Virginia. Neighbors and gym members described the usually safe Logan Circle area as shocked by the violence. Vida Fitness closed its location indefinitely.

Police continue to investigate the precise sequence and any additional planning. The incident underscores how a prolonged housing dispute, financial strain and unresolved grievances can escalate into deadly violence in the heart of the nation’s capital.