Romney's home state was Michigan, making his 4-D exemption as a missionary all but automatic because of the relatively small number of Mormon missionaries from that state. It might have been more difficult in Utah, where the huge Mormon population meant that there were sometimes more missionaries than available exemptions. Most missions lasted two and a half years, as Romney's did.

The deferments for Mormon missionaries became increasingly controversial in the late 1960s, especially in Utah, leading the Mormon Church and the government to limit the number of church missionaries who could put off their military service. That agreement called for each church ward, or church district, to designate one male every six months to be exempted from potential duty for the duration of his missionary work.

Before and after his missionary deferment, Romney also received nearly three years of deferments for his academic studies. When his deferments ended and he became eligible for military service in 1970, he drew a high number in the annual lottery that determined which young men were drafted. His high number ensured he was not drafted into the military.

As the Vietnam War raged in the 1960s, Mitt Romney received a deferment from the draft as a Mormon "minister of religion" for the duration of his missionary work in France, which lasted two and a half years.

Mayo said no records are available from the period that would show how Romney's deferment was handled. But he said he recalled "the conclusion was `we really don't have to worry about [exceeding the quota] because we were never in that situation.' "

By serving as a missionary and being given the deferment, Romney ensured that he would not be drafted from July 1966 until February 1969. Romney's draft record from the time describes him as "minister of religion or divinity student." Mayo said the church would have considered Romney a minister.

Romney, who has said he would have served if he had been drafted, shed some light on his view of the matter in a recent interview with the Globe.

"I really dont recall thinking about political positions when I was knocking at the door in France" as a missionary, Romney said. "I was supportive of my country. I longed in many respects to actually be in Vietnam and be representing our country there and in some ways it was frustrating not to feel like I was there as part of the troops that were fighting in Vietnam."

At the same time, Romney said, he was influenced by the statement of his father, then-Michigan Governor George W. Romney, who said in 1967 that he had been "brainwashed" by US officials about Vietnam. "When my dad said that he had been wrong about Vietnam and that it was a mistake and they had been brainwashed and so forth, I certainly trusted him and believed him," Romney said.

The exemption for Mormon missionaries created controversy at the time. Non-Mormons in Utah filed a lawsuit against the federal government in 1968. The suit was still in court two years later, at a time when "the church and the Selective Service System work hand-in-hand in deferring the missionaries," according to an article from the period published by The New York Times.

Richard Leedy, the lawyer who brought the suit, said in a telephone interview that he did so because "the substantial number of deferments to missionaries made the likelihood of us non-Mormons going to Vietnam a lot more likely."

Separately, Romney's draft service was deferred due to his status as a full-time student for about three years.

Romney registered with the Selective Service in April 1965 but was not considered readily available for military service until December 1970. His name was then put into the lottery based on an individual's birthday, and he drew the number 300 at a time when no one drawing higher than 195 was drafted.

"When Governor Romney's deferment for college and missionary service ended, he made himself available for military service, and his name went into the lottery, but he was not selected," Romney spokesman Eric Fehrnstrom said via e-mail.

Michael Kranish can be reached at kranish@globe.com

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