Dr. Dennis O’Leary, Voice of Calm After Reagan Was Shot, Dies at 85

Dr. Dennis O’Leary, the Washington hospital administrator whose edifying medical briefings delivered in his calm baritone reassured a world shocked by the attempted assassination of President Ronald Reagan in 1981, died on Jan. 29 in Kansas City, Mo. He was 85.

The cause was complications of Parkinson’s disease, his daughter Margaret Guzzaldo said.

For nearly two weeks following the ambush of Mr. Reagan, who was shot on March 30 by John W. Hinckley Jr. while leaving the Washington Hilton Hotel, Dr. O’Leary was the even-keeled spokesman who updated the news media on the president’s prognosis and the condition of others wounded in the attack.

The president’s press secretary, James S. Brady, was permanently disabled after being shot in the head and later became a vocal campaigner for gun control. A Secret Service agent and a Washington police officer were also wounded.

Dr. O’Leary’s role as the spokesman for George Washington University University Medical Center, where he was dean for clinical affairs, was considered all the more impressive because he was a public relations novice who had never faced the press before — certainly not in the numbers he confronted when he reached the microphone-festooned podium in the medical school’s Ross Hall at 7:30 p.m., five hours after the president was wounded.

Some of his initial medical reports on Reagan were later found to have been optimistic. Surgeons who treated him said that the president had been lucky to have received immediate trauma care, that his blood pressure had dropped precipitously and that the bullet had penetrated a little more than an inch from the president’s heart and an inch from his aorta — not several inches as Dr. O’Leary had originally reported.

He later acknowledged that he sometimes had “a little bit less than complete information” when he briefed the news media and assured global audiences that Reagan was never in “serious danger of dying.”

“I tried to be as upbeat as possible without damaging my credibility,” Dr. O’Leary said.

He was an accidental spokesman. The medical center’s chief executive was out of town that day, prompting Dr. Daniel Ruge, the White House physician, and Lyn Nofziger, the presidential assistant for political affairs, to draft Dr. O’Leary to pinch hit. He was not entirely prepared. With Reagan’s motorcade racing to the hospital from the hotel, Dr. O’Leary was informed that “the president” was en route, to which he replied, unfazed — in a town overrun with titled heads of organizations and visiting dignitaries — “The president of what?”

He immediately had to face the press in televised briefings. “They put me at the podium from which microphones of every imaginable size and shape extended in every direction,” he recalled. “It was definitely showtime.”

Misinformation was spreading, including reports that Mr. Brady had died.

Dr. O’Leary told The New York Times that he had never appeared before a television camera as a public spokesman before. Nor had he been directly involved in treating the president. Yes, his father was a journalist, Dr. O’Leary said, and “he taught me my command of the English language, but he didn’t teach me how to do this.”

Dennis Sophian O’Leary was born on Jan. 28, 1938, in Kansas City, Mo. His father, Theodore, was a magazine editor and wrote articles for Sports Illustrated and book reviews for The Kansas City Star. His mother, Emily (Sophian) O’Leary, also worked for The Star.

When Dennis was 7 years old and his uncle Bud was killed in combat during the Allied invasion of France in World War II, his mother’s parents decided on what the boy’s profession would be.

“Grandfather and Grandmother Sophian determined that I was going to become a doctor like Uncle Bud and that one day I was going to join Grandfather Sophian in his Kansas City internal medicine practice,” Dr. O’Leary recalled in a memoir, “Calming America” (2022), which he wrote with his wife, Dr. Margaret R. O’Leary, an emergency medical specialist.

“I was perfectly content with the new plan,” he wrote, “even though I didn’t know what being a doctor meant.”

He received his bachelor’s degree in a pre-med program from Harvard College in 1960 and his medical degree from Cornell University in 1964. He trained in internal medicine and hematology at the University of Minnesota Hospitals (now the University of Minnesota Medical Center) and at Strong Memorial Hospital in Rochester, N.Y.

From 1969 to 1972, Dr. O’Leary fulfilled his military service by heading the blood coagulation unit in the hematology laboratory at the Walter Reed Army Institute of Research. He attained the rank of major. He joined the faculty of George Washington University Medical School in 1972 and was promoted to dean for clinical affairs in 1979.

His reassuring demeanor and command of arcana — and his ability to convey information to laymen and fellow professionals alike — were recognized by his medical colleagues.

From 1983 to 1984, Dr. O’Leary was president of the District of Columbia Medical Society. In 1985, he was enlisted by the American Medical Association, the American Hospital Association, the American College of Surgeons, the American College of Physicians and the American Dental Association to become president of the Joint Commission on Accreditation of Healthcare Organizations.

For 21 years he headed the Illinois-based Joint Commission, the nation’s major association for accrediting hospitals and other health care facilities, building a reputation for making the concerns of patients a priority and imposing performance standards.

“I was tested repeatedly,” he wrote in his memoir, “but the biggest test of all happened when I suddenly found myself center stage as George Washington University Hospital spokesman and de facto White House spokesman following the attempted assassination.”

It was the first time that a president wounded in an assassination attempt was being treated at a Washington hospital. Invoking the lack of crowd control that interfered with the treatment of President John F. Kennedy in Dallas in 1963, Dr. O’Leary wrote: “I didn’t want that to happen to President Reagan at our hospital, and it didn’t.”

He returned to Kansas City in 2007. He was told he had Parkinson’s disease in 2013.

His marriage to Diane Guida ended in divorce. He is survived by three children from that marriage, Emily Egerton and Dennis and Scott O’Leary; his wife of 42 years, Dr. Margaret (Wiedman) O’Leary; two children from his second marriage, Margaret Guzzaldo and Theodore M. O’Leary; and nine grandchildren.

Dr. O’Leary recalled that dispelling rumors and getting straight answers — even from his own colleagues — sometimes proved so challenging that some fabrications became self-fulfilling.

In “Rawhide Down: The Near Assassination of Ronald Reagan” (2011) by Del Quentin Wilber, Dr. O’Leary recalled that during Reagan’s recovery it was announced that the president would be moved to a V.I.P. suite. Except there wasn’t one. Administrators anointed a site, and maintenance crews scuttled to repaint the rooms, install Persian-style carpets and mount artwork.

“It looked for all the world like it had been there for quite some time,” Dr. O’Leary was quoted as saying. But, like so much in the nation’s capital, its status was short-lived. After the president was discharged, the rooms were restored to their bare bones essentials.