AUSTIN, Texas — A Tesla employee who was allegedly assaulted by Austin mass shooter Ndiaga Diagne three months before his deadly rampage has filed a $1 million lawsuit against the electric car company, accusing it of failing to protect workers from a dangerous colleague.
The lawsuit, filed Thursday in Travis County state court, alleges that Diagne violently attacked 65-year-old Lillian Mendoza Brady on December 4, 2025, during a prayer break at Tesla’s Gigafactory Texas facility in Del Valle. Brady only learned her attacker’s identity this week when she recognized Diagne’s face in news coverage of Sunday’s mass shooting that killed three people and wounded 15 others on West Sixth Street. The FBI is investigating the shooting as a possible act of terrorism after Diagne was found wearing a shirt with Iranian regime insignia and had a Quran in his vehicle during the attack.
According to the lawsuit, Diagne was praying on a walking path in a common area at the Tesla facility when he grabbed Brady and threw her to the ground without provocation. Brady’s attorney, Robert Hilliard, said his client suffered neck and back injuries in the assault. “If Tesla had information about Diagne’s violent behavior before he attacked Lillian Brady and failed to act, then not only might her assault have been prevented, it may have been an early warning sign of a far greater danger,” Hilliard told CBS News. The lawsuit alleges that Tesla had knowledge of Diagne’s “volatile temperament and propensity for aggression” but failed to monitor common areas or supervise sanctioned activities. Both Brady and Diagne were among approximately 22,000 employees who worked at Gigafactory Texas last year.
Brady reported the December assault to both Tesla and the Travis County Sheriff’s Office but said the company refused to provide Diagne’s name, preventing her from pressing charges. Hilliard said Brady had never seen Diagne before the day of the assault and was unable to obtain video footage of the incident from Tesla. The Travis County Sheriff’s Office confirmed it investigated the assault but has now closed the case because Diagne is deceased. Austin Police Chief Lisa Davis said Thursday that her department had no prior contact with Diagne before Sunday’s shooting, though Hilliard believes other law enforcement agencies may have been aware of him. FBI investigators interviewed Brady this week about the December incident, according to her attorney. Tesla has not responded to multiple requests for comment about the lawsuit or Diagne’s employment history at the company.
Court records reveal Diagne had a documented history of violence prior to both the Tesla assault and the mass shooting. In 2022, a Bexar County civil court judge found that Diagne had a “history or pattern of committing family violence” and granted his ex-wife sole custody of their two young sons, allowing him only supervised visitation. The same year, Diagne was arrested in Texas following a vehicle collision, according to the U.S. Department of Homeland Security. The lawsuit filed by Brady argues that Tesla should have conducted proper background checks and been aware of these warning signs. “Violence rarely appears out of nowhere,” Hilliard said. “Our lawsuit will examine what warning signs were present, why they were ignored, and why Tesla failed to protect its 65-year-old employee.”
The lawsuit accuses Tesla of negligence for allowing an employee with “known aggressive tendencies” access to common areas with other workers and for failing to warn staff about dangerous personnel. Brady, a Buda resident, is seeking monetary relief exceeding $1 million for physical pain, mental anguish, lost wages, physical impairment and medical expenses. The suit also demands that Tesla preserve all evidence related to the alleged assault, including correspondence, photographs and recordings. “By allowing unsupervised prayer breaks in shared common areas involving an employee with known aggressive tendencies, Defendant breached its duty of care,” the lawsuit states. The complaint further alleges that Tesla’s conduct constituted gross negligence, making the company subject to punitive damages. Hilliard characterized Tesla as “stonewalling” Brady after she brought the assault to the company’s attention.
Diagne carried out his deadly attack early Sunday morning at approximately 1:30 a.m. outside Buford’s Backyard Beer Garden on West Sixth Street, a popular entertainment district. He used a handgun and also had an AR-style rifle with him during the rampage, law enforcement sources told CBS News. The three victims killed were identified as Savitha Shan, 21, a University of Texas business student; Ryder Harrington, 19, a former Texas Tech student; and Jorge Pederson, 30, a mixed martial arts fighter who had recently moved to Austin. Police shot and killed Diagne after he opened fire on the crowded bar patio. The attack left 15 additional people hospitalized with gunshot wounds. A growing memorial of flowers, candles and photographs now honors the victims outside the bar where the shooting occurred.
The lawsuit raises questions about corporate responsibility and workplace safety protocols at major employers. Brady’s legal team argues that Tesla failed to implement adequate safety measures despite having resources and technology capabilities. “It’s just curious to me that a company that claims it can go to Mars has no way of making sure that their employees remain safe from other employees who may be dangerous,” Hilliard said. The case also highlights potential gaps in information sharing between employers and law enforcement agencies when workplace violence occurs. Austin police continue investigating the mass shooting jointly with the FBI, with authorities examining whether the attack constitutes domestic terrorism given the Iranian regime symbolism found at the scene.
