"The self-congratulatory tone of the majority and concurring opinions in last term’s controversial Supreme Court blockbuster, Citizens United v. Federal Election Commission, extended beyond the trumpeting of an absolutist vision of the First Amendment that allows corporations to spend unlimited sums independently to support or oppose candidates for office. The triumphalism extended to the majority’s view that it had imposed coherence on the unwieldy body of campaign finance jurisprudence by excising an “outlier” 1990 opinion, Austin v. Michigan Chamber of Commerce, which had upheld such corporate limits, and parts of a 2003 opinion, McConnell v. FEC, extending Austin to unions and to a broader set of election-related television and radio broadcasts. The majority saw itself as returning the Court to the fountainhead of this jurisprudence, the Court’s 1976 opinion in Buckley v. Valeo."
Rick Hasen's paper on Citizens United
SSRN;Citizens United and the Illusion of Coherence: