Charles Rembar, 85, a writer, literary agent and lawyer who was a champion of First Amendment rights and a forceful voice of those seeking to publish books that were once judged obscene but came to be regarded as works of art, died Oct. 24 in New York. The cause of death was not reported.

Mr. Rembar defended the publishers of D.H. Lawrence's "Lady Chatterley's Lover," Henry Miller's "Tropic of Cancer" and John Cleland's "Fanny Hill" in what were some of the most important censorship cases in American law.

Mr. Rembar argued the "Fanny Hill" case before the Supreme Court in 1965, winning 6 to 3 as the court agreed that the 18th-century novel about an orphan's sexual awakening in a London bordello had literary merit.

Over a six-decade career in New York as a lawyer and sometime literary agent, he represented such writers as Herman Wouk, John Jakes, Michael Dorris, Louise Erdrich and Tom Clancy. One of his first clients was his young cousin Norman Mailer.

Mr. Rembar was the author of books on the law, including the 1968 work "The End of Obscenity," for which he received a George Polk memorial journalism award. In 1975, he published a collection of essays, "Perspective," and in 1980, a history of the American legal system, "The Law of the Land."

He also could explain the law with tongue firmly in cheek, once famously maintaining, "Pornography is in the groin of the beholder." He also explained the inpenetrability of legal jargon as the result of a lawyerly language based on Latin, French, English, "incantation and a bit of mumbling."

Over the years, he also contributed articles on subjects ranging from baseball to the advantages of old age to such publications as Life magazine, the Atlantic Monthly, The New Republic, Esquire and The New York Times.

But he was best known for his work in the censorship cases that lifted bans on books popularly perceived as pornographic.

Mr. Rembar grew up in New Jersey, the son of a cattle farmer and hotelier. He was a 1935 graduate of Harvard University and 1938 graduate of Columbia University law school, where he served as managing editor of the law review. He worked for the Office of Price Administration before World War II, then served in the Army Air Forces during the war. After the war, he began a New York law practice which he was to continue until his death.

He got his start in obscenity law in 1954 when Rinehart & Co. refused to publish Mailer's third novel, "The Deer Park," because of six salacious lines. After Mr. Rembar filed suit for advance royalties, Rinehart settled with Mailer, essentially paying him a fee for the privilege of not publishing his work.

In 1959, Barney Rosset, the head of Grove Press, approached Mr. Rembar, whom he knew from the tennis courts, to try a case for him. It involved Grove's efforts to publish an unexpurgated version of "Lady Chatterley's Lover," which had been banned by the postmaster general for promoting "indecent and lascivious thoughts." Rembar eagerly accepted the challenge of defending a work popularly perceived as well-written pornography which was, he said, "something the courts had always condemned."

The Lawrence novel, which had been published in Italy in 1928, had only appeared in bootlegged versions in the United States. Mr. Rembar defended its frank use of anatomical terms and four-letter words used to describe sexual intercourse. A New York district court judge ruled it was not obscene, a decision that was upheld on appeal in 1960.

A few years later, Mr. Rembar spearheaded the defense of "Tropic of Cancer," which Grove published in 1961. Miller's semi-autobiographical account of his early years and sexual adventures in Paris had been published there in 1934, but in the United States it was blocked by more than 60 court cases in 21 states. The book was eventually published.