Whether he’s representing Britney Spears, Steven Spielburg, or the United States of America as a US Attorney, Mathew Rosengart ’87, says he strives for excellence and humility in all of his work. At an event sponsored by the Sports and Entertainment Law Society, Rosengart returned to his alma mater for a conversation with BC Law students, covering his career from clerking for then New Hampshire Supreme Court Justice David Souter, to becoming a federal prosecutor, to representing celebrity clients in Hollywood as partner in the firm Greenberg Traurig.
Rosengart entered law school knowing he wanted to be a litigator, but told the room that he didn’t have a game plan, and, in fact, didn’t even know what the other career options were. He encouraged students that there’s not a specific thing they should be doing to be set up for “success.” Instead, Rosengart emphasized the importance of working hard and being enthusiastic, no matter how small or even boring the task at hand might be. “The thing that will distinguish you is grit,” he said. Recalling his first case as an Assistant United States Attorney in Florida, he explained that “to me it was the most important case in the country, even though no one knew about it.” Thirty years later, he continues to think of each of his cases as life and death.
Although Rosengart aims to conduct himself the same no matter how well-known his client is, he recognizes that public scrutiny does play an important role in a high-profile case. “You have to be aware of how what you file and what you say will be picked up by the media,” Rosengart explained. “It’s naive to think that the media doesn’t affect the outcome of your cases.” He referenced how social media and news articles that flood the internet can sway public opinion, and, even potentially, the jury. In Rosengart’s view, “there’s no doubt that stuff seeps in.”
Rosengart has his share of experience handling media craze. In 2021, he successfully fought to free Britney Spears from her conservatorship, winning the case in only four months. He talked about walking out of the courthouse and getting to make the call to Spears, a call he had worried could be bad news. Instead, he got to tell her that she’d get to sleep that night for the first time in thirteen years, as a free woman.
How does Rosengart maintain his focus in a global spotlight? He credited his composure to his time at BC Law: “It gave me the initial confidence in my skill set and who I was. The skills you learn here are transferable.” Rosengart has used his skills in both public and private practice, beginning with his time at the justice department where he appreciated their motto of doing justice. “That’s your job as a lawyer,” he explained.
When he transitioned to private practice, it was because he had achieved what he had wanted to do while working for the government, and was looking for something different. An avid consumer of art and movies, when he moved to Los Angeles, the opportunity presented itself for him to combine his legal skill set with his love of entertainment. Just this week, he was named to The Hollywood Reporter’s 2025 Power Lawyers list.
Photograph by Andres Leiva ’26