Warren Leslie, who in 1964 raised hackles in Dallas, his adopted hometown, when he contended in a book that a climate of right-wing extremism had primed the city to become the scene of a national tragedy — the assassination of President John F. Kennedy — died on July 6 at his home in Chicago. He was 84.

Mr. Leslie died of natural causes, his niece Leslie McCullough Jeffries said.

A former reporter for The Dallas Morning News, Mr. Leslie was a vice president and chief spokesman for Neiman Marcus, the Dallas-based luxury department store chain, when he wrote “Dallas Public and Private: Aspects of an American City,” published barely four months after Kennedy was assassinated.

Though never a best seller, the book was widely reviewed as a window on the psyche of Dallas at a time when the country was still struggling to understand and recover from the assassination, which occurred on Nov. 22, 1963. Reprinted in 1998 by Southern Methodist University Press, it remains a document of the era.

“It is an extraordinary thing when an American city does not trust itself to receive the president of the United States in dignity,” Mr. Leslie wrote. “Dallas did not so trust itself — and with reason.”...