Anthony Kennedy

“ Encouraging citizens to vote is a legitimate, indeed essential, state objective; for the constitutional order must be preserved by a strong, participatory democratic process. In short, there is much to be said in favor of California's law; and I might find this to be a close case if it were simply a way to make elections more fair and open or addressed matters purely of party structure.
The true purpose of this law, however, is to force a political party to accept a candidate it may not want and, by so doing, to change the party's doctrinal position on major issues. ”

“ There is a practical identity of interests between parties and their candidates during an election. Our unfortunate decisions remit the political party to use of indirect or covert speech to support its preferred candidate, hardly a result consistent with free thought and expression. It is a perversion of the First Amendment to force a political party to warp honest, straightforward speech, exemplified by its vigorous and open support of its favored candidate, into the covert speech of soft money and issue advocacy so that it may escape burdensome spending restrictions. ”

“ Political parties advance a shared political belief, but to do so they often must speak through their candidates. When the State seeks to direct changes in a political party's philosophy by forcing upon it unwanted candidates and wresting the choice between moderation and partisanship away from the party itself, the State's incursion on the party's associational freedom is subject to careful scrutiny under the First Amendment. ”