D.C. doctor kills manager who was witness in his mold suit

A Washington emergency physician who had spent more than a year suing his condominium association over mold in his penthouse shot and killed the building's manager inside a ground-floor gym on Thursday morning, wounded four people from his seventh-floor balcony and then killed himself.

James Stuart, 46, the manager of the Metropole condominiums in Logan Circle, was shot just before 8 a.m. inside the VIDA fitness center on the building's street level, about a mile north of the White House. Matt Lambert, 55, was found dead in his seventh-floor unit of an apparent self-inflicted gunshot wound, officials said.

Court records show Lambert was in litigation with the building's management over mold and moisture, and investigators believe the shooting grew out of it. "There has been an ongoing dispute between the suspect in this case" and management "regarding maintenance issues, mold and the like. We believe it's related to that," Interim Police Chief Jeffery Carroll said.

What the filings show

Lambert bought the penthouse in September 2016 for $1,095,000, according to District tax records. Court documents show the Metropole Condominium Association began facade work in March 2023, and that water was intruding into his unit by March 2024.

By September 2024, mold was visible and detectable by smell, according to the court documents. An independent inspection by ServPro found "visible mold contamination on exterior and interior walls, due to possible water intrusion." Lambert asked the association to act in October 2024.

Lambert sued the Metropole Condominium Association in March 2025, and by May put his losses above $290,000, CBS News reported. The association and EJF Real Estate Services, the management company, denied causing the damage. In their answer they blamed third parties beyond their control and said Lambert had failed to limit his losses.

Five minutes in Logan Circle

Lambert walked into the gym and shot Stuart, leaving the other people inside unharmed; a federal law enforcement official and a local law enforcement official told NBC News that he had gone there to target a specific person. He then walked out and fired on the street before returning to his unit and barricading himself inside.

Lambert was armed with three guns, Carroll said, and shot four people from his condo patio, three of whom had non-life-threatening injuries. He also fired through his apartment door into the hallway. "This whole incident took place in less than five minutes," Carroll said.

James Spellman, who was in the gym with about 50 other people, said a man fell to the ground within seconds and blood pooled around him. "He was instantly dead. He had been shot in the neck," Spellman said. A fire alarm sounded and members ran, and one of them, Anthony Mirones, said people in the cardio area had to step over the body.

An account called OfMiceandMold

An X account under the name @OfMiceandMold collected complaints about the state of Lambert's apartment, CBS News reported. In dozens of posts the account vented about the Metropole's contractors and EJF Real Estate Services, the management company. At 8:06 a.m., minutes after the gym shooting, it posted what it said was an engineering report on the mold and water problems: "My manifesto is an engineering report." Police have not confirmed that Lambert wrote the posts.

In a post dated April 28, the account said: "If you're looking for the building manager, I would check the gym."

On Oct. 1, the account invoked Luigi Mangione, who pleaded guilty in August to federal charges in the 2024 killing of UnitedHealthcare chief executive Brian Thompson. "After months of 'Luigi' tactics (delay, deny, defend) by the HOA, we were finally able to submit an independent engineering report into the record," the post said, adding that the report would be shared "when the time is right." Mangione had written "delay," "deny" and "depose" on his ammunition.

A witness who was about 20 feet from the shooting and lived directly below Lambert told CBS News that the doctor had grown increasingly upset at homeowners association meetings and used to invite people into his apartment to show them how bad it was.

Stuart's role in the case

Stuart, of northwest Washington, had managed the Metropole for EJF Real Estate Services, and Lambert's attorney, Joel Braithwaite, told reporters that Stuart was a "central fact witness" in the lawsuit and "very pivotal in relaying information to the board."

EJF and the Metropole Condominium Association did not immediately respond to requests for comment from CBS News.

The standoff on the seventh floor

Police negotiators reached Lambert by phone while he was holed up in the apartment, Carroll said, and he fatally shot himself there. SWAT teams and other officers had their guns drawn on the roof of a building and on the ground below. The apartment directly beneath his was left under an inch of water from the response to a fire at the scene, the neighbor told CBS News.

Much of the block of 15th Street Northwest was closed off as police urged people to avoid the area, which includes the gym, St. Luke's Episcopal Church and a Whole Foods store, and nearby schools were locked down. Mayor Muriel Bowser said she was "devastated" by the loss of life in what she called a "senseless act of gun violence."

What his lawyer said

Braithwaite said Lambert had spent more than $300,000 pressing the lawsuit and that the condo resembled a "war zone" because of its condition. He said Lambert had seemed in "great spirits" 48 hours before the shooting and was about to start a new job.

Lambert said in the suit that the problems began after a contractor worked on the building's exterior and that he had not been able to enjoy the penthouse since 2024, The Associated Press reported. The complaint was amended in July, according to NBC News.

Lambert founded and ran MLEM, a healthcare and technology consultancy in the District, according to his LinkedIn profile, and he earned his undergraduate and medical degrees at Marshall University in West Virginia.

Litigation wears on you especially as a plaintiff or as a defendant ... Ultimately, these matters should've been resolved in court.

Speaking to reporters, Braithwaite said he was "deeply shaken and saddened" by the violence. "I don't think there's any sense to be made," he said of the shootings. "I can't give you that closure."

What is still unresolved

One of the four people shot from the balcony was still in critical condition by late Thursday afternoon, Carroll said. The suit Lambert filed over the mold in his penthouse was unresolved when he died, more than two years after he first asked the association to deal with it. If you or someone you know is in crisis, call or text the 988 Suicide and Crisis Lifeline.