Her arrest resulted in his placement in foster care.

“It does seem like a very minor thing, considering what it did to everyone’s life,” he told Ms. Russakoff. “On the other hand, the alternative — staying at home for those years — could have been much worse.”

He and his two older brothers were removed from the family’s tenement in Little Italy and eventually reunited at Woodycrest, a Bronx orphanage run by the American Female Guardian Society and Home for the Friendless. Those last four words, carved in stone, greeted the 120 boys and girls who lived there.

He was reunited with his parents when he was 12, graduated from Seward Park High School and started studying at City College, leaving when he was drafted into the Army during the Korean War. He later enrolled at Bradley University in Peoria, Ill., on the G.I. Bill, and graduated with a degree in civil engineering in 1958.

He earned a degree from Brooklyn Law School, studying at night, on a scholarship, while working during the day for the Society for the Prevention of Cruelty to Children, the very agency that had placed him in foster care.

After serving as an assistant prosecutor under District Attorney Frank S. Hogan of Manhattan, Mr. Scoppetta was appointed investigation commissioner by Mayor John V. Lindsay and reappointed by Mayor Abraham D. Beame. It was the first time in the department’s 100-year history that its chief had been retained by a new mayor. He was also Mr. Beame’s deputy mayor for criminal justice.

Mayor Michael R. Bloomberg named him fire commissioner, just months after the department was devastated by the loss of 343 of its members, who were responding to the terror attacks on the World Trade Center on Sept. 11, 2001.

During Mr. Scoppetta’s tenure, two firefighters died at the Deutsche Bank building in a 2007 fire that exposed serious lapses in the department’s building inspection procedures, as well as lapses by other agencies, and the union took a no-confidence vote in the commissioner after he imposed a zero-tolerance policy toward illegal drug use. However, firefighters’ response times improved and the number of fire deaths declined to a 100-year low.