A workplace assault claim that went unresolved for months has taken on a far darker significance after the coworker accused in the incident was later identified as the gunman in a deadly Austin mass shooting.
The Lawsuit’s Core Allegation
According to court filings, 65-year-old Tesla employee Lillian Mendoza Brady is seeking more than $1 million in a negligence lawsuit alleging she was assaulted inside Tesla’s Austin facility on December 4, 2025, by a coworker later identified as Ndiaga Diagne. Brady claims the assault happened during a prayer break in a common area, when Diagne allegedly grabbed her and threw her to the ground. She says she reported the incident to both Tesla management and the Travis County Sheriff’s Office at the time, but didn’t know her alleged attacker’s name and says she wasn’t given access to facility security footage that could have identified him.
Why the Case Escalated Months Later
Authorities have identified Diagne as the man who drove a black Cadillac SUV into Austin’s Sixth Street entertainment district on March 1 and opened fire on a crowd outside a bar, killing three people and injuring nearly twenty others before officers shot and killed him at the scene. According to the complaint, Brady says she only connected her alleged attacker to the shooting after his name and photo circulated in national news coverage following the attack — realizing, she says, that the man responsible for the mass shooting was the same coworker from the December incident.
That connection is now central to Brady’s lawsuit, which argues Tesla knew or should have known about Diagne’s alleged volatile behavior after the reported December assault and failed to take adequate action before the March shooting occurred. Tesla has not yet responded publicly to the specific allegations, and the claims remain unproven allegations in an active civil case.
A Shooting Still Under Investigation
The March 1 attack triggered a multi-agency law enforcement response, and federal authorities are reportedly examining whether broader motives were involved beyond the immediate incident. That investigation remains ongoing, and officials have not released further detail about what may have led to the shooting.
One More Entry in Tesla’s Growing Legal Docket
Brady’s suit lands amid a broader wave of litigation against Tesla this year spanning both factory operations and vehicle design, including a $51 million claim alleging a factory robot knocked a worker unconscious, a lawsuit over Model S doors allegedly failing to open in emergencies, a separate $1 million Cybertruck Autopilot crash suit, and a workplace injury claim involving roughly 150 pounds of Cybertruck components allegedly falling on an employee. Separate allegations have also surfaced claiming the company favored foreign visa workers over American employees in some hiring decisions.
None of that has slowed Tesla’s production plans at the Austin Gigafactory, one of the company’s largest manufacturing hubs, or CEO Elon Musk’s public ambitions for future manufacturing expansion. But Brady’s case now sits at an unusually heavy intersection of workplace-safety litigation and one of the year’s most high-profile violent crimes, and it will move through the courts as both the lawsuit and the shooting investigation continue in parallel.