New York City mayor Zohran Mamdani has officially sworn in Lillian Bonsignore as the Fire Department of New York (FDNY) commissioner on January 6 in a historic moment, as she becomes the second woman and the first openly lesbian person to hold the role.

Mamdani announced the appointment at a press conference on December 23, praising Bonsignore’s long-standing commitment to public service. A veteran of FDNY Emergency Medical Services (EMS), Bonsignore spent 31 years in the department before retiring in 2022. Her career included frontline service during the 9/11 attacks and senior leadership throughout the COVID-19 pandemic.

“FDNY deserves a leader who cares deeply about the work, because she has done it herself,” Mamdani said at the time. “She is the kind of leader I’m proud to have in my administration.”

However, Elon Musk later took to his social media platform X to criticise the appointment, arguing that Bonsignore had “never served as a firefighter”. Quoting another post, he added: “People will die because of this. Proven experience matters when lives are at stake.”

Mamdani responded swiftly, rejecting the implication that EMS experience was somehow insufficient. He said, “Experience does matter, which is why I appointed the person who spent more than 30 years at EMS. You know, the workforce that addresses at least 70% of all calls coming into FDNY?”

Bonsignore’s record includes serving as chief of the FDNY’s EMS division from 2019 to 2022. During that time, she became the first woman to lead the division and the first woman to achieve four-star chief status within the department. Her tenure was defined by large-scale crises, from the aftermath of 9/11 to the unprecedented pressures of the pandemic.

In a statement to City & State New York, Mamdani highlighted her steady leadership, saying her “calm, decisive approach during COVID-19 when EMS professionals were more vital than ever is exactly what the city needs in moments of uncertainty”.

Bonsignore has also defended her appointment, emphasising her practical knowledge of both EMS and firefighting needs. “I know what the firefighters need, and I can translate that to this administration,” she said. “I’ve been EMS for over 30 years. And now you have a commissioner who could start an IV.”

Despite criticism from Musk, Mamdani has made clear that Bonsignore’s experience speaks for itself, making her the perfect fit for the fire department commissioner, and that inclusive, capable leadership remains central to his vision for New York City.