CHICAGO (CN) – The Seventh Circuit handed a victory to the Libertarian Party on Friday, declaring an Illinois requirement that third parties run a full slate of candidates to get on the ballot unconstitutional.

“We have little difficulty concluding that the full-slate requirement severely burdens the First Amendment rights of minor parties, their members, and voters,” Judge Diane Sykes said, writing for the unanimous panel. “As a condition for ballot access, the requirement forces minor parties to find and recruit candidates for races they want nothing to do with.”

The Illinois Election Code requires new political parties that wish to enter candidates for office in a political subdivision, such as a county or the state, to submit a petition “signed by qualified voters equaling in number not less than 5 percent of the number of voters who voted at the next preceding regular election,” for that subdivision.

In addition, new parties must submit a complete list 134 days before the election, naming a full slate of candidates for offices in the state or county in which it wishes to run.

Established political parties are not subject to either rule, and Illinois is the only state in the nation with a full-slate requirement.

The Libertarian Party challenged the requirement, arguing that it burdens third parties by forcing them to find candidates for offices that might not be important to them, or for which the party might not have a qualified candidate.

The Seventh Circuit agreed Friday, affirming a lower court ruling declaring the requirement unconstitutional.

“The core of the fundamental right to political association is the right to band together in a political party to advance a policy agenda by electing the party’s members to office. That necessarily includes the party’s right to access the ballot and its candidates’ right to appear on the ballot under the party banner,” Sykes wrote in a 12-page ruling.

The judge continued, “For a minor party and its nominees, Illinois’s full-slate requirement extinguishes those rights unless the party fields candidates in races it may want no part of. This is a severe burden on fundamental constitutional rights, and Illinois hasn’t offered a compelling state interest to justify it.”

Illinois justified the law at oral arguments in February by claiming that it is meant to prevent “sham parties” from getting listed on the ballot.

But the Seventh Circuit judges were not convinced.

“By incentivizing minor parties to manufacture frivolous candidacies as a means to an end, the full-slate requirement actually thwarts the interests Illinois invokes,” Sykes said.