Platt lost the Democratic Party primary on June 10, 2008. After his loss in the Democratic primary, the South Carolina Election Commission ("Election Commission") informed Platt that he could not run in the general election on behalf of the Green Party or the Working Families Party pursuant to South Carolina's "sore loser" statute. See S.C. CODE § 7-11-10 (2010). According to the statute, "[n]o one who was defeated as a candidate for nomination to an office in a party primary or party convention shall have his name placed on the ballot for the ensuing general or special election..." Id. Platt, the Green Party, and Robert Dunham, one of Platt's supporters, brought suit against the Election commission, alleging violations of the right of association secured by the First and Fourteenth Amendments of the United States Constitution. The federal district court upheld the "sore loser" statute and granted the Election Commission's Motion for Summary Judgment.

Platt appealed to the United States Court of Appeals for the Fourth Circuit, contending that the sore-loser statute is unconstitutional as applied to the Green Party because he won the Green Party primary election before losing the Democratic primary election. According to Platt, an interpretation of the statute that precludes Platt's candidacy in the general election places a severe burden on the Green Party's association rights. Platt further argues that the application of the statute in that way allowed the Democrats to effectively veto the Green Party's candidate. Platt sought application of the strict scrutiny standard because of the severe burden placed on the Green Party's association rights. Platt contended that the application of the strict scrutiny standard requires a finding that the statute is unconstitutional as applied because the statute is not narrowly tailored to advance South Carolina's interest in "minimizing excessive factionalism."

The Election Commission argued that the Green Party's association rights were not severely burdened and that the strict scrutiny standard is not applicable. The Election Commission further contended that Platt risked disqualification by running on behalf of multiple parties. The Election Commission took the position that South Carolina's sore loser statute serves several regulatory purposes.

In an analysis of whether a state election law impermissibly infringes on rights of association guaranteed by the First Amendment, which applies to the states through the Fourteenth Amendment, the Court weighed the character and magnitude of the burden that the rule imposes on the association rights against the state's interests. Statutes that place a severe burden on association rights are subject to strict scrutiny. Timmons v. Twin Cities Area New Party, 520 U.S. 428, 434 (1997). The court first determined that the burden placed on the Green Party was not severe. The court found that the statute did not require the Green Party to have its nominees selected by members of other political parties. Platt chose to run for the Democratic party nomination and subjected himself to the ensuing consequences. Moreover, the Green Party could have attempted to convince Platt to refrain from running in other primaries. The Court found that Platt's disqualification did not affect the Green Party's ability to nominate another candidate. Therefore, the Court determined that strict scrutiny was not warranted in this case.

The Court then examined the governmental interests that the statute serves. The statute minimizes excessive factionalism and party splintering, minimizes voter confusion, and ensures the orderly, fair and efficient election of public officials. Platt argued that his Green Party nomination did not splinter the Democratic party, but the Court disagreed. The Court found that the timing of Platt's primary loss did not eliminate the potential for factions in the Democratic Party. If his name remained on the ballot, Democratic supporters who voted for him in the primary could have voted for him in the general election. Platt would have splintered the Democratic vote. The Court concluded that the government's interests were served in the application of the sore-loser statute. The Court found the sore-loser statute constitutional and affirmed the district court's ruling.