Irving Philip Seidman, a hard-charging mob prosecutor in Brooklyn turned longtime white collar criminal defense lawyer, who faced off with Rudy Giuliani in a citywide parking violations scandal and who appeared before the U.S. Supreme Court in a landmark case on self-incrimination, has died. He was 83.

He passed away of natural causes Sept. 29 at his home in Princeton, New Jersey, said Gloria Seidman, his wife of 60 years. He had been suffering from Parkinson's disease.

Irving Seidman was known as meticulous, shrewd and honest, and because of his impeccable lawyerly reputation, he became an informal and formal adviser to many in New York's business and legal worlds, said his son, Brian Seidman, who practiced law alongside his father from 1993 to 2010. For years, then-Manhattan District Attorney Robert Morgenthau asked Seidman to privately address newly minted assistant district attorneys on how they should conduct themselves as attorneys, including when they faced compromising choices, Brian Seidman said. Irving Seidman was also for many years counsel to both the estates of Lee Strasberg and Marilyn Monroe.

But he was more widely known for his decade in public service, during which he aggressively tackled organized crime figures and public corruption, and for his more than four decades in private practice, a time when he grew especially proud of his work defending clients' constitutional rights, Brian Seidman said.

“There was no adversary too big or important to challenge 'legally and properly,' as he would say,” recalled Lawrence Silverman, another New York attorney who practiced alongside Irving Seidman, in an email.

Seidman began his legal career in the Kings County District Attorney's Office in 1961, and by 1966, he was appointed head of the Rackets Bureau by then-District Attorney Aaron Koota, his family said. In that role, he won racketeering convictions against mafia figures and bribery convictions against city employees, and he put away police officers for accepting payoffs from gamblers.

In 1971 he moved to private practice, and he did not stop working as an attorney until age 79, Gloria Seidman said.

One of his proudest moments came in 1978, when he appeared before the U.S. Supreme Court in United States v. Jacobs, said Brian Seidman. He represented defendant-appellee Estelle Jacobs, who was caught during a trial, as she testified, lying about having made threats to harm someone and was later indicted.

The Supreme Court let stand a lower court opinion that had dismissed the indictment because Jacobs was never warned about her constitutional rights against self-incrimination. The high court's decision established that a trial witness who is a potential defendant should be informed of that potential upon taking the stand, and should be given full Miranda warnings.

“He considered it a high point of his career to be able to appear before the Supreme Court, in particular in a case where the application of the rule of law was at stake,” Brian Seidman said.

In 1986, Irving Seidman went toe to toe with then-Southern District of New York U.S. Attorney Rudy Giuliani, when he represented Geoffrey Lindenauer, a city Parking Violations Bureau deputy director. Lindenauer had been federally charged in a scandal centered on the extortion of hundreds of thousands of dollars from companies collecting fines for the bureau.

According to Brian Seidman and news accounts, Giuliani needed to turn an involved person into a prosecution witness, and he focused the powers of his office on Lindenauer. Irving Seidman countered with patience and a steely attitude, eventually negotiating a strong plea-bargaining deal for his client.

Said a New York Times profile of Irving Seidman that appeared after the deal was struck, “During two months of intermittent negotiations with Mr. Seidman, Federal and state prosecutors privately described him as a formidable, unpredictable and often unbudging foe.”

Irving Philip Seidman was born in East New York, Brooklyn, in 1934 to Eastern European immigrant parents and was raised in meager circumstances, his family said. At age 12, he wrote down that he wanted to become a lawyer, Gloria Seidman said. Later he was able to attend Brooklyn College free of tuition. He was always grateful, telling young people until the end of his life “that with hard work and perseverance you could overcome and make yourself a better person,” Gloria Seidman said.

He earned his law degree from New York University in 1958.

Brian Sideman said he will remember his father as a “lawyer's lawyer” who “believed not only in the law, but the application of the law to everyone.”

“He would look at every potentiality in a case, and he would evaluate. He would call it 360-degree thinking,” Brian Seidman added.

He also said of the reputation his father built, “My dad made his career on being scrupulously honest and incorruptible—he was a prosecutor going against the mob—and the world of New York, even beyond the world of law, came to know that and would call him for advice and opinions on important matters of ethics.”

“He especially enjoyed being a trial lawyer. He called it being on stage,” said Gloria Seidman.

Seidman is survived by Gloria, of Princeton; Brian, of Dublin, Ireland; his daughter, Ellen, of San Juan, Puerto Rico; his daughter, Lauren Kaltman, of Princeton; and four grandchildren. A funeral was already held.