Michael Busch, the longest-serving Maryland House speaker in the state’s history, died Sunday, his chief of staff said. Busch was 72.

Busch, a Democrat who became speaker in 2003, had developed pneumonia after a follow-up procedure to a 2017 liver transplant. He had been diagnosed with nonalcoholic steatohepatitis, a liver disease. He also underwent heart bypass surgery in September, after experiencing shortness of breath. Chief of staff Alexandra Hughes said Busch was surrounded by loved ones at the time of death.

He was known for his interest in health care, environmental measures to help the Chesapeake Bay and progressive polices. The state approved same-sex marriage and repealed the death penalty during his tenure as speaker. Legislation raising the state’s minimum wage was passed twice during his time in office.

Gov. Larry Hogan, a Republican, said flags will fly at half-staff to honor Busch, effective immediately until sunset of the day of interment. He described Busch as “a giant in our government” and said his legacy is evident in his many legislative achievements.

“Speaker Busch and I came from different sides of the aisle, but we often came together in the best interests of the people of Maryland,” Hogan said. “He served with the decency and good nature of a teacher, a coach, and a family man. I was honored to know him and to work closely with him.”

Alison Prost, the Maryland executive director of the Chesapeake Bay Foundation, highlighted Busch’s environmental work.

“The Chesapeake Bay lost a champion today,” Prost said. “While there were many issues that were near and dear to Speaker Busch, he elevated saving the Bay to a priority for the General Assembly, and legislators followed his lead. He will be sorely missed.”

Busch was first elected to the House in 1986. His district included the state capital of Annapolis, making him a frequent presence in the Maryland State House — even when the General Assembly was not in session.

He was known as a consensus builder and an approachable good listener, qualities that helped him manage the diverse 141-member House of Delegates for as long as he did.

He considered himself a progressive Democrat. He had a strong commitment to equal rights that resulted from growing up in the 1960s during the height of the civil rights movement against racial segregation.

“That was ingrained in me from my grandparents to my parents and through the ’60s,” he told The Associated Press in 2002.