The 9th Circuit Court of Appeals has temporarily blocked illegal immigrants from registering to vote in Arizona using state forms, requiring proof of citizenship for federal elections. This decision, seen as a victory for Arizona Republicans, mandates that state registration forms without documented proof of citizenship must be rejected. However, those using federal registration forms without proof of citizenship can still vote in federal races, including the presidential election. The ruling, which stays an earlier injunction by a lower court, will be in effect until September, pending further appeals. Arizona officials emphasized that this change will not affect the upcoming primary elections as the voter registration deadline has already passed.