Fred Dubois came to Idaho Territory in 1880 with his brother Dr. Jesse Dubois, Jr, who had been appointed physician at the Fort Hall Indian Agency. The younger Dubois—Fred was only 29—spent a few months as a cattle drive cowboy before he got into his preferred career, politics. The Dubois brothers grew up in Illinois. Their parents were friends with Abraham Lincoln. So, Fred Dubois had political connections in Washington, D.C. That smoothed the way for him to become U.S. Marshall for Idaho Territory, a position for which he had no discernable qualifications.
Nevertheless, he embraced the job, especially when it came to arresting Mormon polygamists. He was frustrated, though, because juries of their peers routinely set the polygamists free.
Dubois pushed to get a bill passed in the territorial legislature that would allow him to bring men with multiple wives to justice, even though polygamy was already illegal under federal law. The result was the “test oath.” Under the terms of the law, territorial officials could require an oath of nonsupport of “celestial marriage” before a person could vote, hold office, or serve on a jury. Suddenly a jury of a polygamist’s peers could not include members of the LDS faith. The prohibition was soon ensconced in the Idaho constitution. It was enforced for only a few years but remained in the constitution until 1982.
It wasn’t polygamy itself that Dubois abhorred or the Mormon faith. It was the political power of Mormons he wanted to quell. They tended to vote in a block. In 1880, for instance, every vote in Bear Lake County was for a Democrat.
Politics was very much Fred T. Dubois’ game. He became popular with non-Mormons statewide, and since Mormons could no longer vote, he easily won election as a territorial delegate to the U.S. House of Representatives in 1887. He was elected to the Senate after Idaho became a state, serving from 1901 to 1907.
Thanks to Randy Stapilus for his book Jerks in Idaho History, and Deana Lowe Jensen for her book about Fred T. Dubois, Let the Eagle Scream. I depended heavily on both for this post.