Over the last decade, the five-justice Republican-appointed majority on the Supreme Court has forged a glaring pattern of 5-4 decisions that benefit Republicans at the polls and big corporations pretty much everywhere. In election-related rulings involving issues like gerrymandering and suppression of Democratic-leaning voters; in rulings where it’s corporations versus humans; and, of course, in letting corporate interests to flood our elections with money, it’s been a 5-4 rout in an unmistakable pattern. The upcoming Supreme Court arguments this week in Janus v. American Federation of State, County, and Municipal Employees will tell a lot about this pattern.

At stake is a unanimous decision from 1977 called Abood v. Detroit Board of Education, which let unions collect funds called ”agency shop fees” to cover their cost of doing collective bargaining work that benefits members and nonmembers alike. The Supreme Court has reaffirmed Abood numerous times, more than 20 States have enacted statutes consistent with that case since it was decided, and public entities of all stripes have entered into multiyear contracts with unions following Abood’s guidance. Precedent, unanimity, reaffirmance, and reliance; all of this suggests that the Court would ordinarily uphold this 40-year-old decision.

But Abood has been a thorn in the side of the union-busting right wing, who’ve been plotting its demise for years. Recently, in a case involving public employee unions, Justice Samuel Alito digressed from the issue at hand to raise questions about the constitutionality of these agency shop fees, apparently inviting a challenge to Abood. Justice Sonia Sotomayor saw what was going on. “To cast serious doubt on longstanding precedent,” she wrote in a concurrence, “is a step we historically take only with the greatest caution and reticence. To do so, as the majority does, on our own invitation and without adversarial presentation is both unfair and unwise.”

Michael A. Carvin, a perennial conservative advocate, picked up on the majority’s cue and in the name of a front group called the “Center for Individual Rights” promptly filed the challenge Justice Alito had invited. Carvin actually asked the lower courts to rule against his clients so they could hustle their case up to the Supreme Court (in real litigation, parties don’t often want to lose). That case was called Friedrichs v. California Teachers Association, and it was expected to be the death knell of Abood; but Justice Antonin Scalia unexpectedly died, the Court deadlocked 4-4, and Abood lived on.

It took more procedural shenanigans, over in the Senate, to keep the far-right’s union-busting dreams alive. Friedrichs was certainly in the minds of Senate Republicans stonewalling confirmation hearings for Merrick Garland to replace Justice Scalia. The stakes were high, and Majority Leader Mitch McConnell’s strategy got a big assist from dark political money, including a $17.9 million contribution from a single unnamed donor. At least $7 million went to the campaign against Judge Garland, and later $10 million went to support Neil Gorsuch for that seat.

With Gorsuch in place, it was time for another run at Abood. Janus is the case.

As with the Gorsuch confirmation, dark money was a driving force behind both Friedrichs and Janus. The Friedrichs campaign was underwritten by the right-wing Lynde and Harry Bradley Foundation, which openly states its political goal to “reduce the size and power of public sector unions.” The Bradley Foundation not only bankrolled the “Center for Individual Rights,” but also donated to eleven different organizations that filed amicus curiae briefs. Many are back again in Janus.

Some of these groups are backed by the so-called “State Policy Network”– also bankrolled by the Bradley Foundation, and the Koch brothers — which has an $80 million budget. Its CEO Tracie Sharp hasn’t been shy about her group’s plan: “To win the battle for freedom, we must take the fight to the unions, state by state.” The right-wing groups that are packing the Court to achieve these ends see a new Republican-appointed majority, and believe they can safely assume that their five conservative justices will come down against unions. In out-of-court statements several of the amici have trumpeted the outcome as pre-ordained. But there is a problem.

Our American system of government establishes a system of checks and balances among the federal government’s three branches. One element of this balance is an array of principles demanding self-restraint by judges as they carry out their constitutional tasks (this self-restraint is particularly important for the judiciary, which has lifetime tenure and is not subject to veto).

Chief Justice John Roberts noted in a 1993 law review article that the Constitution’s Article III “case or controversy” clause, and related “standing” requirements, serve as “an apolitical limitation on judicial power.” Of course so does the American judicial tradition of respect for precedent. In Janus, the political desires of the sophisticated and powerful interests who have appeared so often in this saga as parties and amici to attack unions run smack into these elemental principles of judicial self-restraint. The choice is stark.

Earlier this term, during oral argument in the partisan gerrymandering case Gill v. Whitford, Chief Justice Roberts voiced concern about the Court’s “status and integrity” if it were to continually adjudicate political disputes. As he put it:

[I]f you’re the intelligent man on the street, and the Court issues a decision, and let’s say, okay, the Democrats win, and that person will say: ‘Well, why did the Democrats win?’ … . It must be because the Supreme Court preferred the Democrats over the Republicans… . And that is going to cause very serious harm to the status and integrity of the decisions of this Court in the eyes of the country.

Well, welcome to Janus. The Janus case presents itself to the public eye as part of a sustained political effort to overturn longstanding precedent in order to achieve anti-union political goals. While it is expected that a changing of the guard in the executive branch or in Congress may presage new policies, constancy and predictability are expected of the judicial branch. Overruling a precedent based on nothing more than a change in the composition of a court signals serious institutional harm.

The pattern of consistent 5-4 pro-Republican and pro-corporate decisions, often marked by procedural irregularities and well-funded and often anonymous interests bankrolling the litigation, at some point no longer looks to the “intelligent man on the street” like an exercise in impartial adjudication, but rather the exercise of raw political power. Janus will be telling.