Shane MacCarthy, 74, a former government official, trade organization officer and consultant who was chairman of the committee that investigated a 1962 civil disorder here, died of a heart ailment Jan. 14 at Sibley Memorial Hospital. He lived in Washington.

On Thanksgiving Day in 1962, nearly 350 persons in a crowd of nearly 50,000 were injured in disorders at what was then D.C. Stadium. The incident followed the city's football championship game, in which St. John's College High School defeated Eastern High, 20-7.

Mr. MacCarthy, a former head of the President's Council on Youth Fitness, was named by School Supt. Carl F. Hansen to be chairman of a special citizens study committee to investigate the riot. The report, though generally praised, created some controversy with its call for community action to control juvenile vandalism and to prevent racial discord. Mr. MacCarthy received awards for his work with the committee from the American Legion, the Cosmos Club and the Sertoma Club of Washington.

He had done volunteer work with a variety of civic and volunteer organizations, including the Boy Scouts, the D.C. Crippled Children's Society and the Cystic Fibrosis Foundation.

Mr. MacCarthy began his government career with the Agriculture Department in 1934, where he became chief of administrative services. He also worked for the Budget Bureau, the National Defense Commission and the Office of Emergency Preparedness before serving as a Navy lieutenant commander in World War II.

After the war, he worked for the Labor Department and the Central Intelligence Agency before being named executive director of the President's Council on Fitness of Youth when it was established in 1956. He held that post until leaving government in 1961.

In 1962, he became community programs director of the National Lumber Manufacturers Association. He was government affairs director of the Printing Industries of America for 10 years before retiring in 1976.

Mr. MacCarthy was a native of County Cork, Ireland, and moved to this country and Washington in 1925. He received bachelor's and master's degrees from Catholic University and a law degree from New York University. Over the years, he taught political and social science at Catholic and Southeastern universities.

Survivors include his wife, Anna Ruppert MacCarthy, of Washington; five sons, Shane, of Swaziland, Kevin, of New York, Timothy, of McLean, Patrick, of Morristown, N.J., and Michael, of Washington; a sister, Maura Gallivan, of Dublin, Ireland, and seven grandchildren.