On June 17, the Hawaii Democratic Party filed a lawsuit in federal court, seeking to close its primary to all except registered Democrats. Hawaii at this time does not ask voters to choose a party when they register to vote. This is the first time any state Democratic Party has ever filed a lawsuit to close an open primary. In the past, the Republican Parties of Virginia, Idaho, and South Carolina filed such lawsuits.
The Virginia Republican Party lawsuit had some success, and the Idaho Republican Party completely won its case. The South Carolina Republican Party lawsuit is still pending.