In implementing his immigration policies, President Trump has repeatedly faced opponents even more powerful than congressional Democrats—activist federal judges.

A few days ago, it happened again. Judge Michael Simon of the U.S. District Court for the District of Oregon issued a decision halting the Trump Administration’s policy of denying visas to aliens who do not have, or cannot afford, health insurance.

Judge Simon’s decision was an extraordinary example of judicial activism. In order to issue his decision, he had to sweep aside one of the oldest rules in U.S. immigration law—the public charge doctrine. The doctrine is that an intending immigrant who is likely to become a burden on the citizens of the United States—a public charge—must be barred from entry.

The doctrine dates all the way back to the colonial period. It first appeared in 1645 in the laws of the Massachusetts colony. Other colonies would later enact similar laws. After independence, state-level immigration laws enforced the doctrine. In the Immigration Act of 1882, Congress for the first time placed the doctrine in federal law, excluding any immigrant “unable to take care of himself or herself without becoming a public charge.”

In 1996, Congress re-codified this age-old doctrine. 8 U.S.C. § 1182(a)(4)(A) now states: “Any alien who, in the opinion of the consular officer at the time of application for a visa … is likely at any time to become a public charge is inadmissible.”

The Trump Administration’s policy, announced on October 4, 2019, implements the public charge statute perfectly. It’s quite clear that a person who is unable to cover his own medical expenses is likely to become a public charge.

But Judge Simon had to find a way to get around this federal law if he was going to strike down the Trump Administration policy. So he ruled that the Trump policy focused too much on the ability to pay for health care, when the federal statute listed a number of factors that were to be considered in assessing whether an alien might become a public charge.

Judge Simon’s conclusion is at odds with the plain meaning of the law. The statute lists five factors that should be considered in determining whether or not an alien is likely to become a public charge: “(i) age, (ii) health, (iii) family status, (iv) assets, resources, and financial status, and (v) education and skills.” The statute also indicates the other (unnamed) factors may be considered. The natural reading of the law is that any one of those factors might suffice to render an alien inadmissible. In this case, inability to afford health insurance reflects the alien’s inadequate “assets [and] resources.” But Judge Simon effectively rewrote the law to say, “Immigration officials may not rely on any single reason for concluding that an alien is likely to become a public charge.” Judge Simon’s contorted reasoning is typical of an activist judge trying to change the meaning of federal law.

And it doesn’t end there. The Trump Administration also relied on a second federal law in issuing the policy. 8 U.S.C. § 1182(f) gives the President extremely broad power to bar aliens from entering the United States: “Whenever the President finds that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States, he may by proclamation, and for such period as he shall deem necessary … impose on the entry of aliens any restrictions he may deem to be appropriate.” President Trump rightly found that allowing aliens to who cannot pay for their own medical care to enter the United States would be detrimental to tax-paying U.S. citizens.

Judge Simon was even bolder in sweeping aside this federal law. He declared that the federal statute was unconstitutional, as applied in this context. He did so by resurrecting a constitutional theory that has been dead for 70 years – the non-delegation doctrine. In so many words, he ruled that Congress cannot delegate to the President such broad authority to exclude aliens who detrimental to the interests of the United States. Never mind that every president since George Washington has had such authority.

Judge Simon’s erroneous decision will eventually be overturned, if not in the Court of Appeals, then in the Supreme Court. But that will take at least a year. In the meantime, the Trump Administration’s perfectly-legal policy will be suspended.

Not surprisingly, Judge Simon is an Obama appointee. His assertion of judicial power to sweep aside the President’s policy is a troubling reminder of just how dangerous and long-lasting the appointment of a judicial activist can be. Obama’s judges have repeatedly twisted the terms of federal law to block President Trump’s immigration policies, from the travel ban, to DACA, to building the wall. If only Senate Republicans had possessed the fortitude to oppose those judges’ confirmation when they had the chance.

Kris W. Kobach is a candidate for the U.S. Senate. He was the secretary of state of Kansas from 2011 to 2019. Prior to that, he was a professor of constitutional law at the UMKC Law School. An expert in immigration law and policy, he coauthored the Arizona SB-1070 immigration law and represented in federal court the 10 ICE agents who sued to stop Obama’s 2012 executive amnesty. His website is kriskobach.com.