Joanne Reisser, vice president of development for the watchdog group Charity Navigator, said the Leary Firefighters Foundation had a $50,000 deficit in 2007 and received one star for its poor financial performance, the New York Post said Sunday.
"Basically, they're living hand-to-mouth," Reisser said of the foundation's performance. "You can't sustain something like that for long."
Reisser praised the Leary foundation's goal of helping fire departments by providing money and equipment, but recommended financial changes to improve such efforts.
"They have a huge vision, and that's wonderful, but the revenue stream needs to match it," she said.
The Charity Navigator's financial ratings are based on various factors ranging from a group's financial sustainability to its fundraising efficiency, the Post said.
Leary, 52, plays a brave New York firefighter in the FX series "Rescue Me."