Arizona has a terrible history of suppressing Native voters that bears more than a little resemblance to the Jim Crow South; it was one of the states required to get preclearance from the Justice Department to make any election law changes under the Voting Rights Act, until that rule was gutted by the Supreme Court in 2013. The laws that were recently challenged forbid ballot collection by third parties (who had assisted Native voters living in remote places far from polling centers) and invalidate all ballots that go to the wrong precinct. This apparently happens with some regularity among reservation dwellers who do not have a regular street address. This Washington Post article about the obstacles faced by Native voters provides some useful background.
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