A trial starting this week in Phoenix will pit a polygamous religious community against the U.S. government, which claims the community’s public officers discriminate against people who don’t share the sect’s beliefs.

The Justice Department in 2012 sued Colorado City, Ariz., and Hildale, Utah, adjacent border towns populated by members of the Fundamentalist Church of Jesus Christ of Latter-day Saints, or FLDS, which broke away from the mainstream Mormon Church after it rejected polygamy in 1890.

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