After months of growing scrutiny, the Justice Department has launched a civil rights probe of Arizona’s Maricopa County Sheriff Joe Arpaio. Arpaio has been accused of overseeing a discriminatory enforcement of federal immigration laws. He recently made headlines for parading a group of chained undocumented prisoners through the streets of Phoenix before transferring them to the infamous Tent City jail. Last year, a group of Latino activists in Arizona filed a lawsuit accusing Arpaio of racial profiling. The Arpaio investigation is believed to be the Justice Department’s first related to immigration enforcement.