Mr. Carroll joined the university’s polling institute just a year after it was formally established, and he went on to play a major role in transforming Quinnipiac’s image — from that of an obscure college named for a local Indian tribe into that of a university with a trusted and widely quoted national opinion survey.
As a hardened reporter — biting on a pencil, a phone cradled to his ear — Mr. Carroll had a flair for detail and nuance in articles that he seemed to write effortlessly and that he delivered dependably on deadline.
He began his peripatetic career in New Jersey reporting for The Passaic Herald News, The Jersey Journal and The Star-Ledger of Newark. In New York, besides The Times, he worked for The Herald Tribune, The Journal American, The New York Post and New York Newsday.
He was working for The Tribune in 1963 when he was sent to Dallas to assist the columnist Jimmy Breslin and the veteran reporter Robert S. Byrd after the Kennedy assassination, and he was in the basement of the Dallas police headquarters when the nightclub owner Jack Ruby shot Oswald amid a scrum of reporters and photographers.
He later wrote of Oswald: “I may have shouted the last words he was ever to hear: ‘How about it, Lee!’ ”
The Tribune had Mr. Carroll write a first-person account, which landed on the front page.
He also covered Ruby’s murder trial and conviction and helped Melvin Belli, Ruby’s celebrated defense lawyer, write “Dallas Justice: The Real Story of Jack Ruby and His Trial” (1964).
The Texas journalist George Fuermann wrote of that book in The New York Times Book Review that it “expresses the author’s vengeance against the city,” where Belli argued that the shooting had been an act of “unthinking impulse.”
Mr. Carroll wrote another book about the case, “Accidental Assassin: Jack Ruby and 4 Minutes in Dallas” (2014), which sought to debunk the theory that Ruby had been involved in a Kennedy assassination conspiracy.
Known to be cranky but easily amused, Mr. Carroll would often pepper his reporting with wry and iconoclastic asides.
“The best of all possible promises has two elements,” he wrote in 1977. “It involves something thoroughly worth doing, and someone else to do it.”
Covering the swearing-in of Abraham D. Beame as mayor of New York City in 1974 — on the heels of the eight-year run of Mr. Beame’s glamorous predecessor, John V. Lindsay — Mr. Carroll wrote…