Merton Roland Nachman Jr., known as Rod, was born in Montgomery in December, 1923. His father and his mother, the former Maxine Mayer, were proprietors of Nachman & Mertief, a prominent department store.

After graduating from Sidney Lanier High School in Montgomery, Mr. Nachman went to Harvard, where he also earned his law degree, though his education was interrupted by a stint in naval intelligence during World War II. He began his legal career as assistant attorney general for the State of Alabama and later was a partner in different law firms in Alabama.

A prominent figure in Alabama legal circles — he served for a time as president of the Alabama Bar Association — Mr. Nachman became part of history when he agreed to represent L. B. Sullivan, a Montgomery city commissioner who had brought suit against The Times for an advertisement it published on March 29, 1960.

The ad, a full-page request for financial support for the legal defense of the Rev. Dr. Martin Luther King Jr., who had been charged with felony perjury, and more generally for the struggle for civil rights in the South, appeared under the headline “Heed Their Rising Voices,” a phrase taken directly from a Times editorial 10 days earlier.

Mr. Sullivan’s name was not mentioned in the ad, but he contended that he had been defamed because his responsibilities included oversight of the Montgomery Police Department. The ad, he said, implied that the police had responded to civil rights protests with intimidation and violence.

At the time, libel was not considered within the purview of the First Amendment’s protection of free speech and a free press, and in Alabama the standard for proof of libel was simple: It had to be shown that a statement had been published, that it had been about the plaintiff, and that it was defamatory, meaning that it stained the plaintiff’s reputation.

Demonstrable truth was a defense against libel, but the ad had contained minor factual errors. Mr. Nachman, a political moderate who was in favor of civil rights and had represented newspapers in the past, nonetheless recognized that he had a winning case. In the original stages of the legal wrangle, he was right: After a three-day trial, an all-white jury deliberated for two hours and 20 minutes and ruled in favor of Mr. Sullivan, awarding him $500,000 (the equivalent of nearly $4 million today). In August 1962, the Alabama Supreme Court upheld the judgment.

The oral arguments in the case before the United States Supreme Court took place in January 1964. As recounted by the Times columnist Anthony Lewis in his 1991 book, “Make No Law: The Sullivan Case and the First Amendment,” Mr. Nachman told the justices, “We say there was ample and, indeed, overwhelming evidence to support the jury verdict.”

But it was also clear that he understood the legal precipice on which the case teetered. In a eulogy for her father, his daughter Linda Connelly said, “Daddy said to his colleagues and family, ‘Either I will win the case or they will change the law of the land.’ ”

That, too, was prescient. In an opinion written by Justice William J. Brennan Jr., who asserted that the right to criticize public officials was “the central meaning of the First Amendment,” the court ruled unanimously that the Alabama libel standard “abridges the freedom of speech and of the press that is guaranteed by the First and Fourteenth Amendments.”

The court further established the “actual malice” standard by which libel cases would henceforth be judged. A state cannot, the court held, “award damages to a public official for defamatory falsehood relating to his official conduct unless he proves ‘actual malice’ — that the statement was made with knowledge of its falsity or with reckless disregard of whether it was true or false.”

George Freeman, a former Times lawyer, said that he met Mr. Nachman on two occasions when he moderated panels about the case, and that Mr. Nachman accepted his loss in the Supreme Court with good humor and a sense of irony.

“He usually defended newspapers and was a well-educated political moderate, so representing the segregationist Southern establishment in the person of Commissioner Sullivan was unusual for him,” Mr. Freeman said in an email. “But under prevailing law he had a winning case, and it was only because the Supreme Court — to ensure continued reporting by the Northern media on the abuses heaped on civil rights workers in the South — revolutionized libel law that he came out on the losing end.”

In the years after The New York Times Company v. Sullivan, Mr. Nachman often acknowledged that he would rather be famous for a case he won than for one he lost, but he nonetheless understood the import of his work. Toward the end of his life, his daughter Betsy asked him why he had chosen the law.

“Because it solves the problems of mankind and sets the standard of behavior,” Nachman said.

Excerpted from The New York Times Nachman obituary.