Charlie Savage, New York Times, December 8, 2015:
When Donald J. Trump called on Monday for “a total and complete shutdown of Muslims entering the United States,” many legal scholars were aghast and said that such a ban would certainly be struck down by courts as blatantly unconstitutional.
But on Tuesday Mr. Trump clarified his proposal, saying that he would exclude only foreign Muslims, not Muslim American citizens who travel abroad and then seek to come home. That distinction, legal specialists said, made it far less likely the courts would strike it down.
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Several legal scholars who specialize in immigration, international and constitutional law said a policy of excluding all foreign Muslims from visiting the United States would still be “ludicrously discriminatory and overwrought,” as Gerald L. Neuman, a Harvard Law School professor, put it. But he said that it was far from clear that the Supreme Court would block it.
Under a provision of immigration law, Congress has already delegated to the president broad power to issue a proclamation indefinitely blocking “the entry of any class of aliens into the United States” that he or she thinks would be “detrimental to the interests of the United States.” No president has ever used that power in such a sweeping way, but the text provides a potential statutory basis for a President Trump to carry out his plan, specialists said.
Still, if Mr. Trump won the White House and invoked that power as a justification to bar all foreign Muslims, people affected by that policy inside the United States–like a person seeking reunification with a family member, or a university that wanted to invite someone to come speak–could file a lawsuit challenging it.
Several legal questions would be raised by such a policy.
First, as a matter of international law, a treaty the United States has ratified, the International Covenant on Civil and Political Rights, bars laws that discriminate against people because of their religion. It protects “all persons,” not just citizens of a member state.
But any lawsuit invoking that provision of the treaty would face an uphill struggle, the specialists said, because Congress has not acted to make that provision enforceable by domestic courts. So even if Mr. Trump’s policy clearly violated the provision, it is doubtful that the Supreme Court would decide that the treaty provided the judiciary with authority to strike the policy down, the specialists said.
Second, as a matter of domestic constitutional law, barring foreigners from visiting–or even barring the return of green card-holding lawful permanent residents–would be subject to a different legal test.
Because decisions about which foreigners to permit into the country are closely related to issues of foreign policy, the courts have long adopted an extremely deferential approach to reviewing such policies by Congress and the executive branch.
Indeed, for most of American history, including a famous 1889 Supreme Court decision upholding a statute passed by Congress that barred all Chinese people from coming to the United States, courts would not even review such decisions. That changed in the 1970s, when the Supreme Court began holding that it could review them.
But even after that change, the court adopted an extraordinarily solicitous standard: So long as the government cites a reason that sounds legitimate on its face for barring a foreigner from entering the country, the justices will uphold it without further scrutiny.
In practice, since establishing that standard, the Supreme Court has never overturned a decision to deny entry to someone.
