IDAHO REPUBLICAN PARTY v. Ysursa, 765 F. Supp. 2d 1266

Open Idaho open-primary system uses a single primary ballot but voters choose only one party, allowing crossover voting.
Idaho Republican Party (and its chairman Semanko) challenge Idaho statutes governing primary elections as applied to their party.
Court conducted bench trial Oct 13–14, 2010; post-trial briefing followed; parties submitted expert and lay testimony.
Intervenors include independents, AIM, and CUIP; Democratic and Libertarian Parties did not intervene.
Court previously denied summary judgment, necessitating trial to determine if crossover voting in Idaho burdens the GOP’s First Amendment rights.
Court concludes Idaho’s open primary is unconstitutional as applied to the Idaho Republican Party.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether Idaho’s open primary burdens the GOP’s First Amendment freedom of association	GOP	Ysursa	Yes; burden substantial and not narrowly tailored
Whether the burden serves a compelling state interest or merely incidental reasons	GOP	Ysursa	Not narrowly tailored to a compelling state interest
Whether the open-primary regime can be saved by tailoring or switching to a closed primary	GOP	Ysursa	unconstitutional as applied; not saved by mere administrative costs

California Democratic Party v. Jones, 530 U.S. 567 (U.S. Supreme Court, 2000) (open/blanket primaries burden party association; not narrowly tailored to state interests)
Democratic Party of U.S. v. Wisconsin ex rel. La Follette, 450 U.S. 107 (U.S. Supreme Court, 1981) (open primary intrudes on party associational rights)
Burdick v. Takushi, 504 U.S. 428 (U.S. Supreme Court, 1992) (standard for weighing burden vs. state interests in election laws)
Washington State Grange v. Washington State Republican, 552 U.S. 442 (U.S. Supreme Court, 2008) (nonsevere restrictions typically justified; general framework for election-law burdens)