Arizona State Senator Martin Quezada (D-Phoenix) has introduced SB 1057. It would change the presidential primaries from closed to semi-closed. Currently only party members may vote in a presidential primary, but the bill would let independent voters vote in any party’s presidential primary.

It is peculiar that Arizona law already lets independents vote in non-presidential primaries, but not presidential primaries. This causes confusion.

Under the U.S. Supreme Court decision Tashjian v Republican Party of Connecticut, if the Arizona Democratic Party wanted to let independents vote in its presidential primary, it could do that, notwithstanding state law. The decision said that states must let independents vote in partisan primaries, if the party wants to let independents vote in its primaries.