An oligarchy, Webster’s dictionary tells us, is “a form of government in which the ruling power belongs to a few persons.” It’s a shame that the Republican majority on the Supreme Court doesn’t know the difference between an oligarchy and a democratic republic.

Yes, I said “the Republican majority,” violating a nicety based on the pretense that when people reach the high court, they forget their party allegiance. We need to stop peddling this fiction.

On cases involving the right of Americans to vote and the ability of a very small number of very rich people to exercise unlimited influence on the political process, Chief Justice John G. Roberts Jr. and his four allies always side with the wealthy, the powerful and the forces that would advance the political party that put them on the court. The ideological overreach that is wrecking our politics is now also wrecking our jurisprudence.

The court’s latest ruling in McCutcheon et al. v. Federal Election Commission should not be seen in isolation. (The “et al.,” by the way, refers to the Republican National Committee.) It is yet another act of judicial usurpation by five justices who treat the elected branches of our government with contempt and precedent as meaningless. If Congress tries to contain the power of the rich, the Roberts Court will slap it in the face. And if Congress tries to guarantee the voting rights of minorities, the Roberts Court will slap it in the face again.

Notice how these actions work in tandem to make the wealthy more powerful and those who have suffered oppression and discrimination less powerful. You don’t need much imagination to see who benefits from what the court is doing.

Roberts’s McCutcheon ruling obliterates long-standing rules that limit the aggregate amounts of money the super-rich can contribute to various political candidates and committees in any one election cycle. In 2012, individuals could give no more than a total of $70,800 to all political committees and no more than $46,200 to all federal candidates.

The rule is based on a political reality Roberts sweeps aside with faux naivete: Access and power come not just from relationships with individual members of Congress but from strong links to party leaders and party structures. Someone who helps a party keep its majority by contributing to 200 or 300 candidates and Lord knows how many political committees will have a lot more power than you will if you make a $25 contribution in a congressional race.

Roberts writes as if he is defending the First Amendment rights of all of us. But how many people are really empowered by this decision? According to the Center for Responsive Politics, 1,715 donors gave the maximum amount to party committees in 2012, and 591 gave the maximum amount to federal candidates. The current estimate of the population of the United States stands at more than 317 million.

Those using the word “oligarchy” to describe the political regime the Supreme Court is creating are not doing so lightly. Combine McCutcheon with the decision in the Citizens United case and you can see that the court is systematically transferring more power to a tiny, privileged sliver of our people.

I keep emphasizing the word “power” because the Roberts decision pretends that the concept is as distant from this issue as Pluto is from Earth. The philosopher Michael Walzer, in his book “Spheres of Justice,” made the essential distinction: “Freedom of speech, press, religion, assembly: none of these require money payments; none of them are available at auction; they are simply guaranteed to every citizen. . . . Quick access to large audiences is expensive, but that is another matter, not of freedom itself but of influence and power.”

In his McCutcheon opinion, Roberts piously declares: “There is no right more basic in our democracy than the right to participate in electing our political leaders.” This lovely commitment escaped him entirely last summer when he and his allies threw out Section 4 of the Voting Rights Act. Suddenly, efforts to protect the right of minorities “to participate in electing our political leaders” took second place behind all manner of worries about how Congress had constructed the law. The decision unleashed a frenzy in Republican-controlled states to pass laws that make it harder for African Americans, Latinos and poor people to vote.

Thus has this court conferred on wealthy people the right to give vast sums of money to politicians while undercutting the rights of millions of citizens to cast a ballot.

Send in the oligarchs.

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