Lawyers who worked with Michael Armstrong during his decades-long New York career say they'll remember him as an excellent storyteller, an eager debater and a brilliant and generous attorney respected by virtually everyone he encountered.

"He was warm, he was funny, he was so committed to public integrity," said Daniel Horwitz, a partner at McLaughlin & Stern, where Armstrong was of counsel during the last years of his life.

Armstrong, who died Oct. 17 at 86, uncovered widespread corruption in the New York City Police Department as chief counsel to the Knapp Commission in the early 1970s.

"That man had war stories like you just couldn't believe," said Kathy Hirata Chin, a partner at Crowell & Moring who serves on the city's Commission to Combat Police Corruption, which Armstrong chaired until his death.

He could make any story into a great tale, friends and colleagues agreed, but he had an impressive career to draw from. As an assistant U.S. attorney in the Southern District of New York in the 1960s, he led the securities fraud unit and discovered misconduct by a Wall Street financier with ties to then-U.S. Supreme Court Justice Abe Fortas. The investigation eventually led to Fortas' resignation.

Armstrong served as the interim Queens County district attorney in 1973, a role that had been vacated due to another scandal. Speaking about his choice for the DA appointment, then-Gov. Nelson Rockefeller said he hoped Armstrong's courage and integrity would inspire the people of Queens, The New York Times reported at the time.

Rockefeller wanted a DA "who has no links and no political ties to do this job—to re‐establish public confidence in law enforcement," the Times reported. Armstrong, who had only recently finished his work with the Knapp Commission, fit the bill.

Eugene Licker of Ballard Spahr worked with Armstrong for more than two decades and credited him with much of his legal education.

"No one disliked Mike," he said. "No matter what he did, he was always good. He was always fair, he was always honest, he didn't have agendas. He let you know where you stood."

In private practice, Armstrong worked on white-collar criminal defense and corporate investigations. He also served as pro bono counsel to the New York Urban League.

In 2008, then-New York Attorney General Andrew Cuomo launched an investigation into alleged state police corruption, and Armstrong served as one of the investigation advisers. The special counsel who led the investigation, Sharon McCarthy, is now a partner at Kostelanetz & Fink, and she said Armstrong was a mentor to her and many others.

"Mike was feisty … a contrarian. I was always surprised by Mike's take on things," she said, adding that he loved to debate for the sake of debating.

Armstrong demonstrated how to disagree and even go through extended litigation without turning the other side into an enemy, McCarthy said.

"There's a certain elegance to it, and it doesn't mean you're not doing your job," she said. "It just means at core, you are an ethical, good person, and that's what Mike Armstrong was."

Armstrong, who was a fellow of the American College of Trial Lawyers, summed up his work with the Knapp Commission in his 2012 memoir, "They Wished They Were Honest."

He is survived by his partner, three daughters, 11 grandchildren, three great-grandchildren and two sisters, according to his obituary.