Are “Open Primaries” on the Supreme Court Chopping Block?

A recent court ruling could have just set the stage for a broader challenge to open party primaries – a development that may significantly alter political dynamics in more than a dozen states.

Currently, laws governing primary elections vary greatly by state. The earliest states hold their primaries in March, while the latest don’t pick major party candidates until September. States also vary in the type of primary elections they require parties to hold.

In “open” primary states (numbering 14 as of 2026), any voter may request the Republican or Democrat ballot, whatever his or her politics. In “closed” primaries (13 states), only voters who are registered to a certain party are allowed to vote in that party’s primary. There are also “semi-closed” primaries (10 states) where registered party members and unaffiliated voters are allowed to vote and “top-two” primaries, “top-four” primaries, and “blanket” primaries (five states), where all candidates are listed on the same ballot regardless of partisan affiliation. In the remaining 11 states, the parties can choose their own rules for primaries.

Importantly, open primary laws give the widest choice and political influence to those who have committed to neither party.

Colorado, which holds semi-open primaries, provides an insight into the shocking consequences of open primaries. In 2022, unaffiliated voters cast 231,000 ballots in Colorado’s Republican primary, 37 percent of the total. In Denver, Boulder, and Jefferson counties, unaffiliated voter totals have recently outnumbered Republican voter totals in the local GOP’s own primary.

A party whose nominees are chosen largely by nonmembers is not governing itself. Accordingly, the state GOP party sued, arguing that the semi-open primary requirement is an unconstitutional violation of the First Amendment.

Defenders answer that Colorado’s parties can opt out of the law. On paper that is true, if three-fourths of the party’s 500-member central committee agrees to nominate by convention. Colorado Republicans have tried every two years and have always fallen short. In 2023, about 65 percent voted to opt out, and the law let the other third overrule them.

In March, U.S. District Judge Philip A. Brimmer held that threshold unconstitutional, calling it “a severe burden on the major parties’ right to association.”

Brimmer did not order Colorado to exclude unaffiliated voters. His ruling addressed the three-fourths vote required for a party to opt out of the semi-open model. Colorado had made it too difficult for party members to make that decision themselves.

If a three-fourths vote is too steep a requirement to exit the state’s primary framework, a state with no exit at all imposes a heavier burden still. Texas is such a state.

Because Texas voters do not register by party, political parties in Texas cannot know whether their own members chose their nominees. Critics call crossover raiding a myth, but after then-Speaker Dade Phelan, a widely perceived moderate, survived his 2024 runoff election by fewer than 400 votes, his conservative challenger blamed Democrat crossovers for saving him. A Houston Chronicle analysis confirmed that about six percent of that runoff election’s voters had last voted in a Democrat primary, nearly double the usual rate.

The Texas GOP was so incensed by the result that it sued the state over its open primary law, arguing that the open primary forces the Texas GOP (and Texas Democrat Party for that matter) to let voters who oppose its principles pick its nominees. Texas Republican Governor Greg Abbott told this year’s state convention attendees that he will fight to ensure “only Republicans vote in Republican primaries.”

Last month, a federal judge paused the state GOP’s lawsuit, expecting lawmakers to close the primary in the 2027 legislative session.

The Supreme Court hasn’t ruled broadly on the question of open primaries, but it has spoken on select cases. In 1981, it agreed that freedom of association “would prove an empty guarantee” if a party could not keep its decisions among those who share its purpose.

In 2000, it struck down a blanket primary open to any voter in California Democratic Party v. Jones. Writing for the majority, Justice Antonin Scalia called the choice of a nominee “the crucial juncture” at which shared principles become concerted action.

Supporters of open primaries offer three justifications.

The first is moderation and combatting extremist elements within each party. A broader electorate, they say, rewards candidates who appeal beyond a narrow insider base. Perhaps, but it is dangerous indeed to allow the government to interfere in a party’s nominating process for the purpose of excluding supposedly “extreme” voices from the ballot. One person’s “extreme” is another person’s “common sense.”

When the California state government claimed that goal in Jones, Justice Scalia said he could “think of no heavier burden on a political party's associational freedom.” The government has no right to edit a party’s message by editing its electorate.

The opposite scenario proves the point further. In 1984, Connecticut Republicans voted to invite independents into their primary election to grow the party. But a state law mandating closed primaries kept those voters out, and the Democrat-controlled legislature refused to change it. In 1986, in Tashjian v. Republican Party of Connecticut, the Supreme Court sided with the local GOP. If a state may not shut a party’s doors, it also may not force them open.

The second argument that defenders of open primaries cite is fairness. Taxpayers, including unaffiliated voters, help fund party primaries. No one, critics say, should be taxed to fund an election they are barred from voting in. That would be a modern form of taxation without representation.

But taxpayer money gives the state no new power over a primary election. The U.S. Constitution’s Elections Clause already lets states set the “Times, Places and Manner” of congressional elections, but not decide who may help choose a party’s nominee. The Jones opinion rejected the California government’s claim that party nominations are “wholly public affairs that states may regulate freely.” If the subsidy is the problem, end it, and let parties pay for their own nominations or choose by convention.

The third argument is the most serious, and it deserves to be stated at full strength. Most November ballots offer two real choices. If only party members pick them, a citizen who joins neither party has no hand in narrowing the field, and where one party dominates, the primary is the election.

Is it good governance to make party membership the price of helping choose one of the two candidates everyone must then choose between?

I think so.

The club is free and open to everyone. Joining takes a checked box and gives a new member as much say as a lifelong one. A requirement anyone may meet at will is not exclusion. In 1973, the Supreme Court upheld exactly this kind of advance-enrollment rule as a guard against cross-party raiding.

Secondly, every voter keeps the final word. No one is barred from the general election or from backing any candidate on its ballot. A nominee is simply a proposal to the electorate.

And the safe-district argument proves too much. If a party's dominance entitles outsiders to a share of its nomination, its rights shrink as its success grows. The remedy for an uncompetitive district is competition, or independents who join the dominant party and outvote its leadership from within.

Regardless, the Supreme Court has yet to address the dubious constitutionality of traditional open primaries. This could change, however, as the nation remains disjointed on the practice. If developments in Colorado, Texas, or elsewhere progress, the Supreme Court may take a stance in the near future.

The Supreme Court's recent June decision points the same way. In National Republican Senatorial Committee v. FEC, a 6-3 majority struck down caps on parties’ coordinated spending, describing parties as the main way private citizens of like minds work together to “select candidates through a primary or caucus process.” That inference from the court is important. A party cannot exercise its right to support a candidate until it has chosen one, so a right to support implies a right to choose.

In this lawsuit, Democrat Party committees argued that the nation’s Framers were “famously suspicious of parties.” Justice Brett Kavanaugh replied that they were “even more famously suspicious of government suppression of political speech.”

In Federalist 10, James Madison wrote cautiously about political parties, or “the mischiefs of factions,” as he called them. But he also argued that political parties are an inevitable product of human liberty, saying that “destroying the liberty which is essential to a [political party’s] existence” would be a remedy “worse than the disease.”

A political party’s liberty to choose its own nominees is tied directly to citizens’ duty to ensure the government remains of, by, and for the people. When the state decides who picks party nominees, it puts its hand on the very tool citizens use to hold it accountable.