L. Harold Sothoron, 82, a member of the Maryland General Assembly for 16 years and a leader in the old-guard faction of the Prince George's County Democratic Party, died Friday at Manor Care nursing home in Hyattsville. He had suffered from arteriosclerosis.

He served in the House of Delegates from 1935 to 1941, then was a member of the state Senate until defeated for reelection in 1950. During his years in the Senate, Mr. Sothoron, at different times, chaired the finance committee, served as Senate majority leader and was president of the Senate.

He was chairman of the Democratic State Central Committee for Prince George's County during the 1950s.

He challenged Richard E. Lankford, (the incumbent member of Congress), for the Democratic nomination in Maryland's Fifth Congressional District in 1956 and was defeated.

Mr. Sothoron was born in St. Mary's County, Md., and grew up in Charles County. He served in the Navy during World War I. He earned three law degrees at National Law School in Washington and taught law there during the early 1930s.

He maintained a law practice in Upper Marlboro and a 350-acre cattle and tabacco farm near Davidsonville until the early 1970s.

He was a counsel and director of the Citizens Bank and Trust Company of Maryland for more than 25 years. Mr. Sothoron was a member of St. Mark's Catholic Church in Hyattsville.

A member of the District, Maryland and American bar association, he had been admitted to practice law before the U.S. Supreme Court.

Mr. Sothoron had been a grand knight of the Washington Council of the knights of Columbus.

His other memberships included the Elks, Lions, Disabled War Veterans, the American Legion and the legion's 40 and 8.

Survivors include his wife, Eleanor Blanche, of the home in University Park.