A federal judge on Tuesday issued a nationwide preliminary injunction that blocks President Donald Trump from requiring prospective immigrants seeking visas to prove they can get or pay for health insurance.

U.S. District Judge Michael H. Simon found Trump’s Proclamation 9945 “inconsistent’’ with the Immigration and Nationalization Act of 1965. He ruled it was issued without “any properly delegated authority,’’ and little, if any, justification underlying its attempt to link uncompensated healthcare costs to legal immigrants.

“As the text of Article I and more than two centuries of legislative practice and judicial precedent make clear, the Constitution vests Congress, not the President, with the power to set immigration policy,’’ the judge wrote in a 48-page ruling.

Simon also cited the 2018 U.S. Supreme Court ruling in Trump v. Hawaii, which said Congress may delegate certain powers to the president, but the president may not execute those powers in a way that “expressly override (s) particular provisions’’ of the immigration act.

Lawyers for seven people who sued Trump won an emergency order on Nov. 2 that temporarily halted the presidential proclamation from taking effect the next day. They then urged a preliminary injunction be issued to halt the new restrictions while their case moves through court.

The plaintiffs include U.S. citizens in Oregon, California, New York, Massachusetts and Illinois who have or plan to petition the government to sponsor a noncitizen relative for an immigrant visa, as well as foreign nationals applying for immigrant visas.

The presidential proclamation says immigrants applying for U.S. visas will be denied entry into the country unless they can show they’ll be covered by health insurance within 30 days or show they have the financial resources to pay for “reasonably foreseeable” medical costs.

The U.S. Department of Justice is likely to appeal the ruling, its lawyers said in court last week. They had urged the judge to issue a stay of his ruling if he were to grant a preliminary injunction, so they could get direction from the solicitor general on an appeal. Simon said he would not issue a stay, or any hold on his ruling, because that would allow the proclamation to go into effect.

Government lawyers argued in court Friday that the president is trying “to avoid unnecessarily burdening the healthcare system.’’ The president’s proclamation will encourage health care planning and reduce costs to hospitals compensating for uninsured patients, Justice Department attorney August E. Flentje said.

But Simon found their argument weak.

“The Proclamation does not discuss any data or provide any estimate regarding how much of the estimated $35 billion in ‘uncompensated costs’ actually stems from recent uninsured legal immigrants or how often recent uninsured legal immigrants use the nation’s healthcare system,’’ the judge wrote.

In contrast, the plaintiffs’ expert, Dr. Leighton Ku, director of the Center for Health Policy Research at George Washington University’s Milken Institute School of Public Health, found that recent uninsured immigrants use less than one-tenth of 1%, or .06 %, of total American medical resources and only .08 % of emergency room services. When only legal uninsured immigrants were considered, the group included in the president’s proclamation, the numbers would be even lower, according to Ku.

Attorneys from the Portland-based Innovation Law Lab and the Los Angeles-based Justice Action Center, who are representing the plaintiffs, also argued that the immigration act doesn’t allow the president to override what Congress has clearly set out as multiple factors for consular officials to consider when deciding whether a prospective immigrant will become a "public charge,'' or financial burden.

Those factors include a visa applicant’s age, health, family status, assets, resources, education and skills, but nowhere does it say “health insurance’’ should be considered, they argued.

The judge agreed.

“The public charge provision as amended in 1996 mandates that the consular officer or the Attorney General ‘shall at a minimum consider’ all of the enumerated factors,’’ Simon wrote. “This codified the longstanding practice of evaluating the ‘totality of the Circumstances’ of the applicant. That subsection ensures that no one single factor is dispositive.’’

Yet the president’s proclamation does just that, making a prospective immigrant’s ability to pay for anticipated health care a single determining factor, the judge found.

Trump’s proclamation further excludes as permissible health insurance such as Medicaid and subsidized plans under the Affordable Care Act and includes as “approved’’ health care plans many that are legally or “practically unavailable’’ to prospective immigrants, the judge noted.

The proclamation appears to address a problem with no resolution in sight that could last indefinitely, Simon wrote.

“It may only reasonably be interpreted as a categorical exclusion for any affected immigrant who cannot afford health insurance or reasonably anticipated medical costs. Such an indefinite bar to entry is not within the President’s authority,’’ the judge wrote.

The proclamation is anticipated to affect approximately 60% of all immigrant visa applicants.

“The President offers no national security or foreign relations justification for this sweeping change in immigration law,’’ the judge wrote. Instead, it appears the president is attempting to justify the change based on domestic policy.

The plaintiffs have shown they’re likely to succeed on the merits of their claim, that the proclamation is outside the scope of the president’s authority and will cause irreparable harm, the ruling said.

The nonprofit group Latino Network is an eighth plaintiff.

“We are deeply grateful we had an opportunity to be heard and are relieved by the court’s decision,'' said Carmen Rubio, executive director of Latino Network. "Our families belong together and our program participants deserve to have their dignity and rights respected, no matter where they come from. Today we can assure our families, staff, program participants that for now their families are safe from the effects of this discriminatory and abusive health care ban.”

Supporting the plaintiffs in a friend of the court brief are 21 states, including Oregon, as well as the District of Columbia and New York City. They argued that the proclamation would harm immigrants, who “are vital to the economic, civic, and social fabric of our states and city.” They described how family reunification brings economic, social, and psychological benefits, while family separation causes mental and behavioral health issues, lower academic achievement among children, toxic stress, cognitive impairment and post-traumatic stress disorder.

“There is no evidence in the record that immediate implementation of the Proclamation is necessary to help the ‘national interest’ of reducing uncompensated healthcare costs,’’ the judge wrote. “On the other hand, there is significant evidence that allowing the Proclamation to go into immediate effect will have an irreparably harmful effect on Plaintiffs, putative class members, state and local governments, and amici (friends of the court.)''

-- Maxine Bernstein

Email at mbernstein@oregonian.com

Follow on Twitter @maxoregonian

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