James Bernard Horigan, 75, a priest who had served as political science professor, government department chairman and graduate school dean at Georgetown University before retiring in the early 1970s, died of a stroke and heart ailment Aug. 9 at Georgetown University Hospital.

Dr. Horigan, who lived at Georgetown University, was a native of Washington and a 1929 graduate of Gonzaga College High School. He entered the Society of Jesus at the age of 15, spending his noviceship at St. Andrews-on-the-Hudson in Poughkeepsie, N.Y. He was ordained in 1942.

He graduated from Woodstock College in Woodstock, Md., and also pursued studies at St. Louis and Harvard universities. He received a doctorate in political science at the University of London. He taught classics, religion and English at a Catholic prep school in Philadelphia before returning here and joining the Georgetown faculty in 1950.

At Georgetown, Dr. Horigan taught courses in political theory, philosophy and government. He was government department chairman from 1953 to 1959, graduate school dean from 1959 to 1967 and director of university libraries from 1954 to 1970. He retired as professor of political science emeritus.

He was a member of the American Political Science Association, the American Library Association and the Council of Graduate Schools.

Survivors include two brothers, John Clements Horigan of Richmond and Frederick Joseph Horigan of Arlington.

JOHN LEE GIBSON, 50, a consultant and former D.C. parole commissioner who was an unsuccessful candidate for the D.C. Council in 1986, died of an aneurysm Aug. 7 at his home in Washington.

He was defeated by Betty Ann Kane in his 1986 bid for the at-large Democratic Party nomination.

Mr. Gibson was a graduate of Morehouse College in his native Atlanta. Before moving here in 1965, he had spent four years as an assistant program manager with the Southern Christian Leadership Conference.

He was a community organizer with the United Planning Organization in Washington from 1965 to 1967. He then held staff posts with the Justice Department's community relations service and the U.S. Civil Rights Commission before serving as a special assistant to D.C. Mayor Marion Barry in the early 1970s. During that time, Barry served on the D.C. School Board.

Between 1974 and 1982, Mr. Gibson was a management analyst with the D.C. Office of Personnel and then an administrative officer with the D.C. Department of Housing and Community Development. He served as a parole commissioner for four years before running for the D.C. Council. He had been a consultant since 1986.

Mr. Gibson had served on the citizens advisory board to the D.C. Bar Association. He was a member of Mount Gilead Baptist Church in Washington.

Survivors include his wife, Ruby D., and two daughters, Stacey and Eva Gibson, all of Washington; two sons, William, of Atlanta, and Julian, of Washington; his father, Calvin H. Sr., of Washington; three brothers, Calvin Jr., of East Orange, N.J., James, of Manhasset, N.Y., and Benjamin, of Atlanta.

LEONARD W. JOHNSON JR., 55, a physician and Air Force colonel who was evacuation coordinator for Project Homecoming, which brought Vietnam prisoners-of-war home in 1973, died Aug. 1 in a plane crash in Howard County, Ind.

Col. Johnson, who lived in Olney, was flying to Indiana where he planned to visit relatives. Howard County Sheriff J.D. Beatty told the Associated Press that Col. Johnson was the only person aboard the single-engine private plane, which crashed during a severe thunderstorm. Police said preliminary findings indicated that the crash was weather-related.

Col. Johnson was born in St. Augustine, Fla., and graduated from high school at age 14. He earned a bachelor's degree in chemistry and a medical degree at Howard University and a master's degree in public health at Harvard University. He also was a graduate of the Air War College.

He entered the Air Force in 1958 and served tours with medical evacuation units in the Philippines during the Vietnam War and also held posts at air installations in West Germany. From 1976 to 1981, he was deputy surgeon and chief of aerospace medicine at the Tactical Air Command at Langly Air Force Base.

He was associate dean of the medical school of the Uniformed Services University of the Health Sciences at Bethesda from 1981 to 1985. Since that time, he had been surgeon general of the Electronics Security Command at Kelly Air Force Base in San Antonio.

Col. Johnson was a command surgeon and aeronautical chief flight surgeon and was certified in aerospace medicine. He was a diplomate of the American Board of Preventive Medicine and a member of the American and National medical associations.

Survivors include his wife, Evelyn, and a son, Leonard W. III, both of Olney; a daughter, Karen J. Carter of Nashville; his parents, Vera Brooks and Leonard W. Johnson Sr., and two brothers, Levar and Vernard, all of Elkhart, Ind., and a grandchild.

JENNIFER JOHNSTON DAVISON, 39, a lifelong area resident who lived in Chevy Chase, died Aug. 7 at a hospital in New Britain, Conn., as a result of injuries she had received in a single-car accident earlier that day.

Mrs. Davison, who lived in Chevy Chase, was traveling to Maine to visit family when the accident occurred. She was accompanied by her two daughters, Lindsay L. and Cameron T. Davison, and a Davison family domestic employe, Gracielo Legulzamon, 28, of Arlington.

A spokesman for the Connecticut state police said the car, driven by Legulzamon, was traveling on I-84 near Plainville when the driver attempted to change lanes, discovered the new lane was already occupied, swerved back to her original lane then lost control of the car. The car turned over several times, hit a guard rail and went down an embankment, police said. Mrs. Davison, who was not wearing a seatbelt, was ejected from the vehicle.

The spokesman said Mrs. Davison was pronounced dead at New Britain General Hospital. The others were treated for minor injuries and released, police said. The accident is under police investigation.

Mrs. Davison, a Washington native, was a graduate of Sidwell Friends School and a 1970 graduate of Mount Holyoke College in South Hadley, Mass. At Sidwell Friends, she was active in the parents' association and did volunteer work for annual fund-raising drives.

In addition to her daughters, of Chevy Chase, Mrs. Davison's survivors include her husband, Robert V. Davison, also of Chevy Chase; her parents, Warner R. and Bobby Johnston of Days Ferry, Md., and a sister, Wendy J. Sinton of Englewood, Colo.

NELLE BYRNE JABLONKA, 81, an area resident since 1979 who had served as vice president of the senior citizens' group at St. Leo's Catholic Church in Fairfax, died Aug. 6 at her home in Fairfax after a heart attack.

Mrs. Jablonka was a native of Texas and graduate of Texas Christian University. She had taught elementary school in Texas, New York and Florida for about 18 years before retiring in 1970. She moved here from Florida.

She had been secretary of chapter No. 752 of the American Association of Retired Persons in Fairfax.

Her marriage to Frank A. Jablonka ended in divorce.

Survivors include a daughter, Mary Hollingshead of Fairfax, and a grandchild.