WASHINGTON, D.C. --Acting Attorney General Sally Yates, a Democratic appointee, says she's directed Justice Department attorneys not to defend President Donald Trump's executive order on refugees.
Yates said in a memo Monday that she is not convinced that Trump's order is lawful, or that its defense is consistent with the department's obligation to "always seek justice and stand for what is right."
Yates was appointed deputy attorney general by President Barack Obama. She became acting attorney general once Loretta Lynch left the position.
Her directive will be in place until she leaves the department, which will happen once the Senate confirms Sen. Jeff Sessions, Trump's pick for attorney general.
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The legal fight over President Donald Trump's ban on refugees is likely to turn on questions of a president's authority to control America's borders and on whether the new immigration policy unconstitutionally discriminates against Muslims.
Civil liberties advocates have challenged the order, which temporarily suspends immigration from seven countries and the United States' broader refugee program. It has drawn nationwide protests since the order was issued on Friday.
Federal judges in New York and several other states issued orders that temporarily block the government from deporting people with valid visas who arrived after Trump's travel ban took effect. Washington state's attorney general announced Monday he's suing Trump over the order.
And the Council on American-Islamic Relations is also arguing in a lawsuit that the ban violates the First Amendment's bar of preferential treatment for a religion - by appearing to favor Christian over Muslim refugees.
"While this ban does not apply to all Muslims, it only applies to Muslims," said Gadir Abbas, one of the council's lawyers. "That type of religious gerrymandering is illegal."
The court cases are only beginning, and legal experts are divided as to whether courts will find Trump's action constitutional.
Federal law gives the president unconstrained power to suspend the entry of "any class of aliens" if he determines their entry "would be detrimental to the interests of the United States." But a different law prevents discrimination against the issuance of an immigrant visa based on a person's nationality or place of birth.
"Historically, the courts have not tried to regulate the executive branch's determination as to who's allowed to enter the country," said Eric Posner, a University of Chicago law professor. "The immigration statute gives the president very broad discretion to block people from entering the country," including for national security reasons.
Posner said he expected judges to give the policy more deference if the administration can show that it was done to protect national security, rather than for political reasons.
He also said courts could find it compelling that the executive order is temporary rather than permanent, and that it does not cover all Muslims from all countries, notably omitting Saudi Arabia - the home nation for the majority of Sept. 11 hijackers.
"The fact that he lets in Muslims from Saudi Arabia tends to undermine the theory that he's acting out of animus," Posner said.
Trump isn't the first American leader to apply a different standard to Saudi Arabia. Its status as the world's leading oil producer and close U.S. ally has led Republicans and Democrats to often overlook its woeful human rights record and spotty history in fighting terrorism. The travel ban applies to Syria, Iraq, Iran, Libya, Somalia, Yemen and Sudan.
Courts have a long history of upholding portions of immigration law that discriminate on the basis of race and nationality, said Peter J. Spiro, a law professor at Temple University. As far back as 1889 the Supreme Court upheld the exclusion of Chinese laborers, and more recent rulings have also upheld similar discrimination.
The court, for example, ruled in 1953 that a noncitizen trying to enter the U.S. has no right under the Constitution to challenge the government's decision to deny entry. That case involved a legal permanent resident of the United States who traveled abroad to Hungary for 19 months. He was denied re-entry because the government said he posed a threat to national security.
But that case and others were decided at a time when the public was more accepting of discriminatory policies.
Adam Cox, a law professor at New York University, said it's historically been challenging to prove that a policy was enacted with the purpose of disadvantaging a particular religion or race, often requiring "smoking gun evidence of the state of mind of the people" behind it. He said that though courts in the past have sustained discriminatory policies, it could be possible for a judge in this instance to "pierce the veil" and decide that the executive order was motivated by animus.
"If a court gets to the point where it sees this as open discrimination on the basis of religion or race, at that point I would part company with people who argue that simply by virtue of this being an immigration policy, it is insulated from constitutional attack," Cox said.
It's also possible that federal judges could be more likely to push back in light of the massive public backlash over Trump's ban, Spiro said.
"If there's going to be a case in which a constitutional challenge has some chance of succeeding, this is it," he said.