Dr. Robert J. Mahon, internal medicine physician, dies

Dr. Robert Joseph Mahon, a Baltimore internal medicine physician who ran St. Joseph Medical Center, died Tuesday, Nov. 20, of heart and kidney failure at St. Joseph. He was 90.

He was the third of six children born to a Bethlehem Steel worker and a secretary living in Sparrows Point.


He graduated from Sparrows Point High School in 1945 and joined the U.S. Navy, working on a minesweeper in the Mediterranean.

After he was honorably discharged in 1947, he attended the University of Maryland, College Park on the G.I. Bill and was an All-American lacrosse player. He wore the number 41, in honor of his father, who had died in 1942 of meningitis when he was 41 years old.


In 1952, he married Ann Gibson, who was also from Sparrows Point. His friend and colleague Mike Matejevich said Dr. Mahon often referred his marriage of 66 years as “the best decision of his life.”

The two had four boys, all of whom followed their father by playing lacrosse in high school and college.

“To my brothers and I, he was everything,” said his youngest son, Michael Mahon. “He came from not a lot at all but love in his family to have an extremely successful professional career. He was a titan.”

Michael Mahon said his father’s desire to become a doctor stemmed from his “genuine desire to help people.” He said he was an especially strong Catholic who had considered becoming a priest, “and then he met my mother.”

His wife said he was a “great man who had a great life.”

Dr. Mahon finished his pre-medical studies in three years and then attended the University of Maryland School of Medicine in Baltimore.

He opened a private practice in 1960 in Towson as an internal medicine physician. For the next four decades, he treated several members of the clergy, including the Sisters of Mercy and the School Sisters of Notre Dame and several executives from Stanley Black & Decker and Baltimore Gas & Electric, among others. He had admitting privileges at Mercy and St. Joseph hospitals, becoming the chief of staff at Mercy Medical Center and the chief doctor at St. Joseph Medical Center.

He became the vice president of medical affairs at St. Joseph Hospital in 1982 and then its chief operating officer in 1990.


After he went to St. Joseph, he cut his practice significantly, but kept treating several longtime patients for 10 to 15 hours a week.

“He worked seven days,” said his son Michael. “He always visited his patients in the hospital. If they were there at midnight, he was there. He was completely devoted to his patients.”

Libby Liberatore, the chief nurse at St. Joseph for several years while Dr. Mahon was chief doctor, said he was “very well respected” and an “excellent” internist and administrator “who was the kind of person who spoke to everyone — people in the cafeteria, hospital workers, janitors. He treated everybody as a person.”

While at St. Joseph, Dr. Mahon spearheaded a significant expansion of operations and facilities, including an open-heart surgery program, a skeletal dysplasia program, a primary care program, a retina center and the O’Dea office building. The cardiac catheterization lab is named after him in honor of his work expanding the hospital’s open-heart surgery services.

Matejevich said Dr. Mahon helped the hospital grow from a community hospital to a regional medical center with national and international reputation by recruiting specialists from Johns Hopkins Hospital and the University of Maryland Medical Center.


“He was known as someone who could get the job done,” said Mr. Matejevich, who knew him for 35 years. “People wouldn’t leave the confines of Johns Hopkins to a community hospital and gamble their reputation unless they had a peer like Dr. Mahon to talk to and relate to and make things happen in their respected programs.”

All the while, he was a deeply devoted father who tried to make all of his sons’ lacrosse games.

“Unless there was an emergency or sickness with one of his patients, he was there,” said his wife. He even rented a plane once so he could see one son play an away game in New York and get back in time to see another son play in Towson, she said.

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Dr. Mahon also enjoyed vacations in Ocean City, golf, and attending Mass every day.

After retirement, his son Michael said, he would go to the Perpetual Adoration Chapel at the Church of the Immaculate Conception in Towson, where he would keep company with the Eucharist for one hour beginning at 2 a.m. on Sunday. Then he would go have Dunkin’ Donuts. “Coffee and two old fashions [donuts],” he said.


“He had a great sense of humor,” his son Michael said, “up until the day he died.”

He recalled getting a call from his father that day. The previous weeks had been difficult, he said, and he had wanted to go home from the hospital, but he couldn’t. “He called me and joked, ‘Mike, somebody kidnapped me and they brought me to this hospital. I want to go home.’ ”

“He was a gifted man,” his son said. “The Lord gave him a lot, and he gave it all back.”

Dr. Mahon is survived by his wife and their four sons, Robert J. Jr., Kevin P., William F. and Michael J. Mahon, all of whom live in the Baltimore area; his brother, Charles D. Mahon of Ellicott City; and nine grandchildren.

A funeral Mass will be offered in St. Joseph Church, 100 Church Lane, Cockeysville, at 11 a.m. on Monday, Nov. 26.