EDMONTON, Alberta >> A sociologist who refused to be sent to internment camps that kept more than 100,000 Japanese-Americans captive during World War II has died in the Canadian city of Edmonton.

Gordon Hirabayashi, who died at the age of 93, was vindicated four decades later when a U.S. court in 1987 overturned his conviction and concluded that the U.S. government’s internment policies had been based on political expediency, not on any risk to national security.

Hirabayashi had by then left the United States, working in Lebanon and Egypt before taking a job at the University of Alberta as chairman of the sociology department.

His son, Jay Hirabayashi, said on Facebook that his father died Monday morning. He said his mother, Esther Hirabayashi, 87, died about 10 hours later. The couple was divorced.

Gordon Hirabayashi was born in Seattle and attended the University of Washington. As a student there, he was one of the first to challenge the U.S. government policy.

In 1942, five months after the Japanese bombed Pearl Harbor, he turned himself in to the FBI and was sentenced to 90 days in prison, a verdict that was upheld on appeal through to the U.S. Supreme Court.

According to a University of Washington newsletter from 2000, Hirabayashi was in his senior year when he refused to get on a bus that was taking Japanese-Americans to internment camps on the West Coast.

"I wasn’t a rebel looking for a cause," Hirabayashi said at the time. "In fact, I was preparing to go. But in the days before I was supposed to leave, I realized that I couldn’t do it."

He said he knew his parents might be in jeopardy, as they had not been eligible for naturalization when they immigrated to the United States.

"But the second generation, my generation, were U.S. citizens," Hirabayashi said. "We had constitutional rights. I didn’t think anything could happen to us. We had a rude awakening."

His disbelief continued as he fought his legal battle, with the help of the American Civil Liberties Union.

"When the case got to the federal courts I thought I might win it, since the primary goal of federal judges was to uphold the Constitution," he said. "But the judge told the jury, ‘You heard the defense talking about defending the Constitution. That’s irrelevant. The issue is the executive order that the military issued.’ Under those circumstances, the jury came back very fast."

Having his conviction overturned many years later was a real vindication not only for Hirabayashi but for "all the effort people had put in for the rights of citizens during crisis periods."

He said it also changed his view of his home country.

"There was a time when I felt that the Constitution failed me," he said.

"But … the U.S. government admitted it made a mistake. A country that can do that is a strong country."

Hirabayashi spent 23 years at the University of Alberta before retiring in 1983. His focus was the study of peasants in developing countries and the problems of confronting the mounting impact of post-Second World War industrialization.

Jay Hirabayashi called his father "an American hero."

"Besides being a great father … (he) taught me about the values of honesty, integrity, and justice," he said.

He noted that though his parents were divorced, "they somehow chose to leave us on the same day."