Chief Justice John Roberts’s chief concern should be upholding his oath to “support and defend” the U.S. Constitution. In most cases, he abides by that oath. But Americans could be forgiven for sometimes thinking that his chief concern is not being the “umpire” he promised to be in his confirmation hearings, but rather going to bat for the judicial branch.

At a public event in Buffalo, New York, on Wednesday, Roberts did a little of both.

I’ll start with where he got things right. When discussing court precedents, Roberts pointed to specific numbers showing that his Court overturns fewer decisions than any Court since the 1950s, but he argued that overturning precedent is not always bad. “I mean, aren’t you glad that, you know, Brown v. Board of Education overruled Plessy [v. Ferguson]?” he asked rhetorically. “The idea that it’s invariably a bad thing to overrule precedent is, I think, quite mistaken.”

If he were braver, he would have touted Dobbs v. Jackson Women’s Health Organization, which overturned Roe v. Wade, one of the most legally atrocious decisions the Court ever rendered, never mind the 62 million babies who died in its wake. To overturn that decision 49 years later, the justices had to withstand intimidation unlike anything they supposedly fear from the Trump administration.

Roberts got it mostly right with this part, with some caveats that I’ll get to: “The judiciary is a coequal branch of government, separate from the others with the authority to interpret the Constitution as law, and strike down, obviously, acts of Congress or acts of the president,” Roberts said. “Its job is to, obviously, decide cases but, in the course of that, check the excesses of Congress or the executive, and that does require a degree of independence.”

He added that the balance of power “doesn’t work if the judiciary is not independent.”

Yes, Article III establishes the judiciary as a coequal branch. It’s part of the Founders’ brilliant design of a system with separation of powers, complete with checks and balances — revolutionary ideas at the time. However, it wasn’t until the 1803 Marbury v. Madison decision that judicial power to have the final word in striking down acts of Congress was established.

The following year, President Thomas Jefferson, a critic of the ruling, warned that the judiciary could become “a despotic branch.” In 1819, he argued that the Constitution could become a “mere thing of wax in the hands of the judiciary.” Indeed, the Court, as the final arbiter of what’s constitutional, often usurps Congress’s role as the first among equals.

Back to Roberts, he’s absolutely correct about the judiciary’s separate role of interpreting the Constitution. The precedent set by Marbury has been widely accepted (and often reaffirmed by the courts), so, at least in that sense, he’s right about the striking down part, too.

Yet there is a growing sense that maybe — just maybe — judges are taking things too far, especially when it comes to striking down actions taken by this particular president. This is where Roberts falls short.

In March, President Donald Trump suggested that impeachment might be in order for DC District Court Judge James Boasberg after the judge ruled against the administration in a deportation case. Roberts issued a statement obliquely referencing Trump’s comment: “For more than two centuries, it has been established that impeachment is not an appropriate response to disagreement concerning a judicial decision. Normal appellate review process exists for that purpose.”

At the time, I wrote: “With Democrats in the minority and rudderless, activist judges have taken it upon themselves to block him at every turn. In two short months, Trump has lost court cases regarding firing executive workers, canceling executive expenditures (like funding gender mutilation of children), reworking executive agencies such as USAID, and deciding how executive agencies will enforce laws such as birthright citizenship or deportation of terrorist sympathizers and criminal terrorists. Just yesterday, yet another power-hungry district judge blocked the commander-in-chief’s order determining criteria for serving in the Armed Forces, saying he must allow ‘transgender’ people to enlist and remain in the military. By the way, when appointed in 2023, that judge became the ‘first LGBT person’ to serve as a district court judge in DC.”

Trump’s legal defeats have continued to mount in the nearly two months since then.

Asked again yesterday about impeachment of judges, Roberts echoed his March comments, saying, “Impeachment is not how you register disagreement with a decision.”

That’s oversimplifying the objections. Boasberg isn’t just issuing decisions Trump and his supporters don’t like; he’s micromanaging and usurping executive authority. Other district judges are doing likewise with sweeping nationwide injunctions against clear executive functions. Aren’t the branches supposed to be coequal and independent? If courts can strike down laws passed by Congress or acts by a president, what’s the recourse for the Article I and Article II branches if they believe it is the Article III branch running afoul of the Constitution?

Roberts hasn’t addressed this, but he should. He should quit publicly rebuking the president and instead rein in lower-court judges who exceed their authority.

Frankly, whenever Roberts opines about the roles of the three branches, I’m reminded of what I consider his most egregious decision — the 2012 decision rewriting ObamaCare so he could save it. Not only did he fail to “check the excesses of Congress or the executive,” he exceeded his own authority to validate the excesses of Democrats.

That is not a problem with the system the Founders designed. It’s an utter failing of people elected or appointed to roles within that system.

My caution to the president is that the more he rails against judges and pushes the envelope in what become territorial battles, the less likely he may be to find allies on the Supreme Court. John Roberts seems intent on sending that signal.

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