Mark John Davis, 56, a government lawyer who had worked on the staffs of several Congressmen, died Oct. 6 at Johns Hopkins University Hospital in Baltimore. The cause of death was complications from liver failure.

Davis, a resident of Greenbelt, Md., had joined The Financial Planning Association in January, serving as assistant director of government relations. His federal service started in 1974, when he joined the Department of Justice’s Law Enforcement Assistance Administration as a legislative counsel. Davis went on to serve in the offices of former Indiana Rep. Vance Hartke (D) as a staff assistant, former California Rep. Frank Riggs (R) from 1995-98, and Rep. Lee Terry (D-Neb.) from 1999-2000. He was legislative director and legal counsel for Terry, and fulfilled both of those roles, as well as deputy chief of staff, for Riggs.

Davis grew up in Washington, D.C., graduating from Wilson High School in 1966. He finished his studies in political science at Albion College in Michigan in 1970 and graduated from Georgetown Law School in 1973. Davis also received a master’s in legislative affairs from George Washington University in 1987.

Steven Sutton, Rep. John Kline’s (R-Minn.) chief of staff and a close friend of Davis, described him as a professional and “a go-to guy,” whose patience with those around him was matched by his intelligence. “He was absolutely brilliant, but he also had wisdom,” Sutton said. “There are a lot of brilliant people in this town, but Mark was one of the few with true wisdom.”

He is survived by his wife of 33 years, Constance Kerns Davis; his son, Matthew Davis; and a sister.