John E. O'Neill, 86, the Washington representative and general counsel of the Small Brewers' Association from 1945 until he retired in 1966, died of congestive heart failure Nov. 21 at Suburban Hospital in Bethesda.

Mr. O'Neill, who lived in Chevy Chase, was born in Ogden, Utah, and grew up in Butte, Mont. He moved to Washington in 1917 and went to work at the old War Department. He also earned a law degree at Georgetown University.

When Prohibition was passed in 1919, he went to work for the Federal Prohibition Commission. From 1922 until 1933, he was a senior attorney in the commission's New York office.

With the passage of Repeal in 1933, Mr. O'Neill returned to Washington and went to work for the Federal Alcohol Control Administration. This later was absorbed into the Bureau of Internal Revenue. Mr. O'Neill remained there until World War II, when he went to work for the War Production Board. He later established the Washington office of the Small Brewers' Association.

Mr. O'Neill was a member of the parish of Blessed Sacrament Catholic Church.

His wife, Celestine, died in 1979. Survivors include a son, Thomas E., of Bethesda, and five grandchildren.