John S. Carroll, the former top editor of the Lexington Herald-Leader, Baltimore Sun and Los Angeles Times, in 1996. (Perry Thorsvik/Baltimore Sun)

John S. Carroll, who guided the Los Angeles Times, Baltimore Sun and Lexington Herald-Leader in Kentucky to Pulitzer Prizes and who was considered one of the most distinguished and inspiring newspaper editors of his time, died June 14 at his home in Lexington, Ky. He was 73.

The cause was Creutzfeldt-Jakob disease, a rapidly progressing neurological disorder that was detected in January, said his wife, Lee Carroll.

During a four-decade career, Mr. Carroll became known as a quietly forceful leader who instilled a sense of journalistic ambition and civic purpose in the papers he edited — even with increasing competition from the Internet and diminishing resources.

In the 1980s, when Mr. Carroll was editor of the Lexington Herald-Leader, his paper challenged the recruiting practices of the powerful University of Kentucky basketball program.

Later in Baltimore, he sent reporters to Africa to expose modern-day slavery in Sudan.

In Los Angeles, he led his paper to 13 Pulitzer Prizes in five years, only to resign in protest in 2005 against staff cutbacks and other pressures imposed by the paper’s corporate parent.

Before he turned to editing, Mr. Carroll was a war correspondent in Vietnam and covered the Middle East and White House as a reporter with the Sun. In Vietnam, he worked alongside Eugene L. Roberts Jr., then of the New York Times. After Roberts became executive editor of the Philadelphia Inquirer in 1972, he hired Mr. Carroll as an editor.

In Philadelphia, Mr. Carroll directed investigations that won the Pulitzer Prize in consecutive years, including a 1977 series on police brutality written by Bill Marimow and Jonathan Neumann.

“John had a real gift for distilling the essence of a story,” Marimow, who later became Mr. Carroll’s managing editor in Baltimore and is editor of the Inquirer, told The Washington Post. “He really was a visionary when it came to seeing broad, deep stories where others, including me, saw something much more finite.”

Marimow recalled that Mr. Carroll guided the series through multiple revisions and, one day, asked the reporters to take a break and meet him in the company cafeteria in 30 minutes. During that time, Mr. Carroll wrote the provocative lead of the series’s opening story:

“It can be said with certainty that two things happened in the 22 hours between Carlton Coleman’s arrest and his arraignment last October.

“One is that he was interrogated by homicide detectives. The other is that his health went from good to poor.

“When it was all over, he spent the next 28 days hospitalized for injuries of the abdomen, arms, shoulders, chest, calf, spine and back.”

Mr. Carroll left Philadelphia in 1979 to become the top editor of the Lexington Herald, which soon became the Herald-Leader after a merger.

He sought to make the Herald-Leader the best of its size in the country and supervised investigative stories about weaknesses in the Kentucky public schools that led the legislature to pass reforms.

A 1985 series about questionable recruiting practices of the basketball program at the University of Kentucky, by Jeffrey Marx and Michael York, won a Pulitzer Prize for investigative reporting.

In unearthing the basketball scandals — which included payments, free clothes and other illegal gifts to potential players — the Herald-Leader challenged one of the most cherished institutions in the state. Journalists received death threats and bomb scares, and a gunshot was fired into the press room.

After taking charge of the Baltimore Sun in 1991, Mr. Carroll reanimated the staff with new hires and a fresh emphasis on investigations and innovative storytelling.

Tall, silver-haired and invariably described as “courtly,” Mr. Carroll had a slight Southern drawl and “a wry expression that rarely changes,” New Yorker media writer Ken Auletta wrote in 2005. “Much like Gene Roberts, he led with an almost gnomic intelligence.”

He sometimes seemed disengaged from the mundane stories of daily journalism, but he had a knack for transforming a nugget of news into a major blockbuster story with far-reaching implications.

When Mr. Carroll learned that slavery was openly practiced in parts of Africa, he gave two Sun reporters $10,000 and sent them to Sudan, where they purchased the emancipation of two people who had been enslaved.

He initiated another series in 1997, after a story about aging ships that had been sent to the scrap yard. Mr. Carroll gave Sun reporters Will Englund (now of The Post) and Gary Cohn 18 months to travel the world as they uncovered examples of environmental degradation and dangerous conditions in the largely unregulated industry.

Their series, “The Shipbreakers,” won the Pulitzer Prize for investigative reporting in 1998, the same year Mr. Carroll was named editor of the year by the National Press Foundation.

Despite his success in Baltimore, Mr. Carroll began to chafe under financial restrictions imposed by the paper’s parent company, Times Mirror of Los Angeles. He was prepared to leave the Sun to lead a journalism foundation in Cambridge, Mass., when Times Mirror was sold to the Chicago-based Tribune Co. in 2000.

The previous year, top executives at the Times concocted a plan to publish a special section about a new Los Angeles sports arena, the Staples Center, and to share advertising profits with the arena’s owners.

It was a blatant violation of journalistic ethics and led to the departure of the Times’s editor and publisher. Tribune executives asked Mr. Carroll to come to Los Angeles to take over the embattled newspaper.

Mr. Carroll sought to revive the spirits of a shell-shocked staff and transform the Times into “a national paper from the West,” on the same level as the New York Times, Wall Street Journal and The Washington Post.

He expanded the paper’s national and international coverage and brought fresh talent to the newsroom, including a new managing editor, Dean Baquet, from the New York Times.

In 2003, Mr. Carroll created a stir that echoed beyond his newspaper when he faulted front-page coverage of a legislative measure in Texas that required abortion doctors to advise patients of a possible risk of breast cancer.

Although the scientific evidence for such a link was minimal at best, Mr. Carroll felt the story appeared to deride the view of the measure’s proponents. He wrote a blistering memo in which he told his staff to maintain a strict stance of neutrality in tone and content.

“I want everyone to understand how serious I am about purging all political bias from our coverage,” he wrote. “We are not going to push a liberal agenda in the news pages of the Times.”

During a 2003 gubernatorial recall election in California, Mr. Carroll and his paper were accused of political bias after publishing a story in which 16 women complained of groping or harassment by Republican candidate Arnold Schwarzenegger.

The explosive story appeared five days before the election, prompting complaints that the newspaper was trying to influence the outcome.

Mr. Carroll adamantly denied the charges, saying the paper would have been negligent if it had not published its investigation. Schwarzenegger won the election, and the controversy quickly passed.

During Mr. Carroll’s five years in Los Angeles, the Times won 13 Pulitzer Prizes in a variety of categories, from criticism to photography to investigative reporting. But his goal of building a world-class paper began to come into conflict with the tightening purse strings of its owner, the Tribune Co.

Amid new challenges from the Internet, Mr. Carroll trimmed 200 positions from the newsroom and had to make do with an ever-shrinking budget. When the Times won five Pulitzers in 2004, Tribune executives did not attend the ceremony.

Frustrated by continual calls for more cutbacks, Mr. Carroll resigned in 2005. When he announced his decision to the newsroom, he received an appreciative ovation that went on for minutes.

His managing editor, Baquet, threatened to walk out with him, but Mr. Carroll persuaded him to stay for the sake of the staff. A year later, when Baquet resisted further cuts to the newsroom, he was forced out by Tribune executives. He is now the executive editor of the New York Times.

John Sawyer Carroll was born Jan. 23, 1942, in New York City. His father, Wallace Carroll, was a foreign correspondent who eventually became editor and publisher of the Winston-Salem Journal in North Carolina.

Mr. Carroll grew up in Winston-Salem and later in Bethesda, Md., while his father worked in the Washington bureau of the New York Times.

He graduated in 1959 from Bethesda-Chevy Chase High School and in 1963 from Haverford College in Pennsylvania. He began his newspaper career in Providence, R.I., before serving two years in the Army.

He was a longtime member of the Pulitzer Prize board and was a fellow of the Academy of Arts and Sciences.

Mr. Carroll’s first marriage, to the former Kathleen Kirk, ended in divorce.

Survivors include his wife of 29 years, the former Lee Huston Powell of Lexington; two daughters from his first marriage, Maggie Vaughan of New York City and Kathleen C. Strathmann of Chevy Chase, Md.; three stepchildren, Huston Powell of Austin and Griggs Powell and Caroline Powell, both of Lexington; three sisters, Margaret Carroll of Appleton, Wis., Posi Carroll of Kentfield, Calif. and Patricia Carroll of Arlington, Va.; and nine grandchildren.

After leaving the Los Angeles Times, Mr. Carroll was a visiting lecturer at Harvard’s John F. Kennedy School of Government and often spoke about the changing fortunes of modern-day journalism.

Having spent years trying to bridge the cultural gap between the newsroom and corporate ownership, he concluded that “the two sides look at each other as separate tribes.”

Corporate executives, he said in a 2006 speech, believed that employees should be dedicated to improving the company’s bottom line.

“The journalist believes that he or she works not for the shareholder primarily, but for the reader and for the public,” Mr. Carroll said. “I think journalists — good journalists — have always looked upon themselves as public servants.”