Citizens of California adopted Proposition 198. Prop 198 changed the California partisan primary from a closed primary to a blanket primary. All people who were registered to vote were thus entitled to vote for any candidate regardless of the candidate’s political affiliation. Ps, who were composed of the Democratic Party, the Republican Party, the Libertarian Party, and the Peace and Freedom Party all sued to prohibit such a primary. The District Court held that the burden on association was not a severe one and was justified by state interests. The Ninth Circuit affirmed.