The Rev. Joseph Doty, 75, a priest, an educator and a former headmaster of Georgetown Preparatory School in Bethesda, chaplain of the National Cathedral School for Girls in Washington, and headmaster of St. Stephen's School in Alexandria, died Sept. 21 at a hospital in Salisbury, England. He had a stroke.

Father Doty was a former Roman Catholic priest and a Jesuit who in 1968 left the Jesuit order and the Catholic Church and resigned as Georgetown Preparatory School's headmaster. "I love the Catholic Church and I always will, but I felt I needed more freedom to think out religious positions than I could have in the Roman Church," he said at the time.

A year later, he married Joy Billington, a reporter for the Evening Star newspaper in Washington, and was automatically excommunicated. His desire to marry, he said, hastened his departure from the Catholic priesthood. "But I'm sure I would have eventually left anyway," Father Doty said.

In 1970, he was received into the Episcopal priesthood at a Eucharistic service celebrated by the Right Rev. William F. Crieghton, who was then the Episcopal bishop of Washington.

He began his chaplaincy that fall at National Cathedral School for Girls, where he had been teaching Latin for a year. He later became assistant head at National Cathedral. He was headmaster at St. Stephen's, an Episcopal School, from 1976 to 1980.

Father Doty was born in Baltimore and entered the Jesuit novitiate at 17. For seven years he studied at Woodstock College in Maryland. In the early 1950s, he began his career in education at Georgetown University. He was ordained a priest in 1957 after passing oral and written examinations, which then were conducted entirely in Latin.

For seven years, beginning in 1961, he was headmaster at Georgetown Prep. This was a period of social turmoil in the United States, including restive race relations, an increasingly active civil rights movement, protests against the war in Vietnam, and broad-based challenges to authority on several fronts.

Within the Catholic Church there was increasing discontent, especially among younger priests, with what was perceived as a rigid and inflexible ecclesiastical hierarchy, and the church lost a number of priests over such irreconcilable differences.

His decision to leave the Catholic Church, Father Doty said, was connected with his thinking on such doctrinal issues as birth control and papal supremacy. As headmaster at Georgetown Prep, he said, "I should have been a witness to Catholic doctrine. But I found that I couldn't be such a witness and also be honest to myself."

He had no intention, he said, of giving up the priesthood. "I always intend to be a priest, but not in the Roman Church."

In 1969 and 1970, Father Doty was active at St. John's Episcopal Church in Georgetown and at St. Stephen and the Incarnation Episcopal Church, 16th and Newton streets NW, where his 1969 wedding to Joy Billington was described in a London Daily Telegraph headline as a "Way Out American Wedding."

As a teacher at National Cathedral School, Father Doty -- his black Labrador, Bart, at his side -- taught beginning Latin to eighth-grade girls. As chaplain, he and Ms. Billington, who covered foreign embassies for the Star, encouraged students to mix with their friends from Washington's international community. Years later, they would recall evenings around a piano with National Cathedral girls singing vigorously with the likes of the Episcopal bishop of Washington and the press attache from the Soviet Embassy.

In 1980, after four years at St. Stephen's School, Father Doty returned to St. John's in Georgetown as interim rector, then served as rector at St. Margaret's Episcopal Church in Washington.

From 1985 to 1989, he was the priest in charge of music at St. Ninian's Cathedral in Perth, Scotland. In 1989, Lord Spencer, the father of the Princess of Wales, invited him to minister in Northamptonshire churches, over which he had patronage. Until he retired in 1993, Father Doty served the parishes of Church Brampton, Halestone and East Hadden.

In retirement, Father Doty and Ms. Billington divided their time between Washington, where they maintained an apartment, and Wilton in England. He was an adjunct clergyman at St. John's in Georgetown and at churches in England.

Survivors include his wife, of Washington and Wilton; a sister, Ann Happel of Eldersburg, Md.; and a stepson, Nigel Billington of France.