The Fire Department is often described as a family, and in the days after the attack on the World
Trade Center, it reacted like one, as firefighters rushed to rescue colleagues, share the burden of
grief and regroup after devastating losses.

But even as the events of Sept. 11 strengthened those bonds, it did little to soften the bitter feelings
that many firefighters have long held for Fire Commissioner Thomas Von Essen. Indeed, on Saturday
night, when Mr. Von Essen took the stage at a benefit concert at Madison Square Garden, many of
several thousand firefighters in attendance joined in sustained booing.

The commissioner was not alone. Senator Hillary Rodham Clinton and the actor Richard Gere also received
their share of scorn. But to the audience of the nationally televised broadcast, for whom Mr. Von Essen had
become the human face of a department celebrated for its dedication and heroism, the hooting was a stunning moment.

"He didn't deserve it," said Tara Stackpole, the widow of Capt. Timothy Stackpole, a decorated fire
officer who died at the trade center. Ms. Stackpole was watching from a corporate box in the arena.
"He has put his heart and soul into the department," she said. "He is heartbroken. It was totally bad
timing. That should have been put aside for the night, especially with the situation we are in now."

Even some of Mr. Von Essen's harshest critics, who acknowledge he was personally devastated by the loss
of 343 firefighters, said the booing was unfair. But they also said that Mr. Von Essen's unpopularity was a
problem of his own creation, the stubborn residue of five years in which he has butted heads with many
firefighters, officers, emergency medical technicians and the unions that represent them.

"The E.M.S. people have been unhappy with Von Essen for years," said Robert Ungar, a spokesman
for the emergency medical technicians' union. "This crisis wasn't going to change that."

To Mr. Von Essen's defenders, he is a strict manager who brought more accountability to the
department, made training more rigorous and pushed to reduce response times by fire companies and
ambulance crews. In the process, they said, he upset the comfortable routines of some chiefs and
former colleagues in the firefighting ranks, where he served for 26 years.

His detractors, on the other hand, have said that Mr. Von Essen, who served as president of the
firefighters' union until his appointment as commissioner, evolved into a dictatorial administrator who
was vindictive toward his critics and condescending to his troops. "They are furious with him," said
Thomas DeParma, the Queens trustee for the firefighters' union. "They don't appreciate Von Essen
being on TV and comparing them to high school seniors, like he is the principal."

Mr. Von Essen's penchant for being painfully direct was evident during an interview with "60 Minutes"
on Sept. 19. He was unsparing in his praise for the bravery and dedication of his firefighters. Then,
toward the end, when asked about department morale, he said: "The guys love what they do. They
complain a lot, but they love what they do. I haven't had time to — I told anyone who's got a problem
to suck it up and move on."

Critics point to the remarks as evidence of Mr. Von Essen's disdain. His supporters said the critics
ignored the broad message of respect.

"He is hard-working and caring," said James Boyle, the former president of the firefighters' union.
"He has a hard edge to him, but it has been misinterpreted. I guess he hasn't always been too careful
about choosing his words."