In 2014 on this website I wrote a blog article: The Supreme Court's Judicial Activism role in Campaign Finance Reform
You don't have to read it. It gets into the details of how corporations became to be recognized as "people" under the law although there is no mention of corporations at all in the Constitution. But I also wrote about how the later Supreme Court 5-4 decisions have overturned prior Supreme Court decisions. Here are some extracts:
1976: Buckley v. Valeo: In this landmark case, the Supreme Court struck down parts of the Federal Elections Campaign Act of 1974 including provisions that limited expenditures by campaigns, individuals and groups, and by a candidate from personal funds. The court's decision was a recognition that money counts as speech, since "virtually all meaningful political communications in the modern setting involve the expenditure of money." The case was the first in a chain of decisions over the next 38 years that allowed corporations, organizations and rich individuals to use their money to influence elections.
2010: Citizens United versus the Federal Election Commission: Justices Scalia and Kennedy, supported now in their 5-4 majority decision by conservative Justices Thomas, Roberts and Alito, not only reversed the court's 1990 Austin, Michigan decision but also rolled back parts of McCain Feingold as restricting free speech. Essentially the court prohibited the government from restricting political independent expenditures by corporations, associations and labor unions. Justice Stevens was particularly incensed by the reversal on the Austin, Michigan case, and within his 90 page dissent he chastised the court for expanding the scope of the arguments beyond what was being specifically litigated in Citizens United.
Stevens writes somewhat sarcastically, "Our colleagues’ suggestion that “we are asked to reconsider Austin and, in effect, McConnell ,” ante , at 1, would be more accurate if rephrased to state that “we have asked ourselves” to reconsider those cases." Stevens goes on in his dissent:
"The conceit that corporations must be treated identically to natural persons in the political sphere is not only inaccurate but also inadequate to justify the Court’s disposition of this case.
"Congress has placed special limitations on campaign spending by corporations ever since the passage of the Tillman Act in 1907…The Court today rejects a century of history when it treats the distinction between corporate and individual campaign spending as an invidious novelty born of Austin v. Michigan Chamber of Commerce.
". . . corporations have no consciences, no beliefs, no feelings, no thoughts, no desires. Corporations help structure and facilitate the activities of human beings, to be sure, and their 'personhood' often serves as a useful legal fiction. But they are not themselves members of “We the People” by whom and for whom our Constitution was established.
2011: Arizona Free Enterprise PAC v. Bennett: On June 27, 2011, the Roberts Supreme Court made another egregious ruling (again 5-4) to throw out a provision of Arizona’s 13 year old well regarded public campaign financing system. The concept for matching funds in Arizona has several well documented positives that seemingly avoid the legal pitfalls of the free speech arguments...or so it seemed. Note that in 1976, an earlier Supreme Court in Buckley vs Valero upheld public financing as Constitutional. Times have changed and the make-up of the court has changed.
Justice Roberts wrote the majority opinion that the Arizona law was unconstitutional because it “plainly forces the privately financed candidate to ‘shoulder a special and potentially significant burden’ when choosing to exercise his First Amendment right to spend funds on behalf of his candidacy.” For many legal scholars including the ACLU, the Roberts opinion defied logic.
Justice Kagan didn't mince her words in writing the dissent: “Except in a world gone topsy-turvy, additional campaign speech and electoral competition is not a First Amendment injury... Arizona, remember, offers to support any person running for state office. Petitioners here refused that assistance. So they are making a novel argument: that Arizona violated their First Amendment rights by disbursing funds to other speakers even though they could have received (but chose to spurn) the same financial assistance. Some people might call that chutzpah.”
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I'll leave it at that. The point I was making in 2014 was that the Supreme Court has been highly politicized in their interpretations of the Constitution, and that prior Supreme Court findings can serve as precedent for other cases only until they are challenged again in the courts. Later Supreme Court rulings can overturn prior Supreme Court decisions and can even engage what is termed "judicial activism" -- going beyond the remit of the case to make law.