Would Donald Trump’s proposed ban on Muslims in the U.S. be constitutional?

Donald Trump speaks during a rally coinciding with Pearl Harbor Day at Patriots Point aboard the aircraft carrier USS Yorktown in Mt. Pleasant, S.C., Monday, Dec. 7, 2015. (Photo: Mic Smith/AP)

Republican presidential frontrunner Donald Trump’s call to bar Muslim immigrants from the United States, a nation founded by immigrants, does not just offend American sensibilities — it could violate U.S. law, according to experts.

Laurence H. Tribe, a professor of constitutional law at Harvard Law School and co-founder of the American Constitution Society, said Tuesday that Trump’s proposed ban would be illegal, exceptionally difficult to implement and damaging to national security.

“Donald Trump’s plan to ban all Muslims from entering the U.S. — even as recently pulled back to make exceptions for U.S. citizens abroad, whether in the military or otherwise, who happen to be Muslims — would be illegal and therefore unconstitutional, as well as being a nightmare to administer,” Tribe said in an email to Yahoo News.

There was immediate backlash Monday when the Trump campaign called for “a total and complete shutdown of Muslims entering the United States until our country’s representatives can figure out what is going on.”

According to Tribe, such a prohibition would imperil our national security and give the ISIS terrorist group its greatest possible propaganda victory against the U.S. and its allies around the world. Jihadists routinely exploit anti-Muslim prejudice to attract new recruits to their cause.

In the United States, the First Amendment guarantees freedom of religion and prohibits governmental preferences among religions. Furthermore, the Fifth Amendment guarantees due process and equal protection under the law to all people, not just all U.S. citizens.

Many law experts say that Trump’s proposed plan would violate freedoms protected by the U.S. Constitution. (Photo: Aleksandar Nakic/Getty Images)

“For Trump’s absurd and wildly un-American plan to be adopted would require either that we suspend the U.S. Constitution, which not even a formal declaration of war by Congress would accomplish,” Tribe continued, “or that we formally amend the U.S. Constitution to remove, or carve a gaping hole in” the aforementioned amendments.

Leti Volpp, professor of law at UC Berkeley School of Law, agreed that there is no way that categorically barring Muslims from entering the country could be legal.

The Trump campaign initially indicated that the ban would apply to Muslim-Americans traveling abroad but he recent backpedaled on that position. Either way, these experts say it won’t fly.

“Trump says this would cover citizens overseas. Citizens have a right to enter the country of their citizenship. In terms of noncitizens, while the political branches are given some deference in crafting exclusion laws, that deference is not absolute, and this would violate the Constitution’s guarantee of equal protection, not to mention the guarantee of freedom of religion,” Volpp said in an email.

U.S. Citizenship and Immigration Services has instructed officers who are conducting interviews with applicants for immigration benefits not to inquire about their religious beliefs.

“Avoid questions about a person’s religious beliefs or practices unless they are relevant to determine the individual’s eligibility for a benefit,” a policy memorandum reads. “Do not make any comments that might be taken as a negative reflection upon any other person, race, religion or country.”

But not all constitutional scholars are of the same mind on this issue.

Eugene Volokh, a law professor at UCLA School of Law, said that the issue of constitutionality for Trump’s proposal is not as cut–and–dried as others would have you believe, citing the Supreme Court’s plenary power doctrine.

“Plenary power refers to the court’s view that Congress and the president together have basically unlimited authority regarding whom to admit to the country. That’s seen as a fundamental element of sovereignty that the Constitution does not constrain,” he said in an interview with Yahoo News.

He cited the 1972 SCOTUS decision Kleindienst v. Mandel that found the federal government had the right to refuse someone’s entry into the U.S. (Belgian academic Ernest Mandel was blocked entry due to his Marxist beliefs.)

According to Volokh, deferring to plenary power to justify discrimination against Muslims is grotesque and awful but not necessarily unconstitutional.

“This is not something that the courts would clearly strike down,” Volokh said. “That I wouldn’t be so sure of. They might and they might not.”

During times of crisis, historically speaking, greater numbers of people have willingly forfeited their civil liberties – or denied the rights of others – in the name of security.

This dates back to the dawn of the nation. Even the Founding Fathers were divided over their interpretations of the Constitution.

In 1798, the United States was engaged in an undeclared naval war with France and suspicion spread throughout the country. President John Adams signed the Alien and Sedition Acts in part so the government could deport any foreigners it deemed dangerous. Then-Vice President Thomas Jefferson vehemently opposed the bills and accused Adams of undermining the Constitution.

History has been on Jefferson’s side and Supreme Court rulings in the mid-20th century have spoken of the Alien and Sedition Acts as exercising “power not delegated by the Constitution” and “one of our sorriest chapters.”

There are other dark chapters in U.S. history when ethnicity or country of origin were used as the basis to deny immigrants from entering the country.

In 1882, President Chester Arthur signed into law the Chinese Exclusion Act, which prohibited the immigration of Chinese laborers. It was repealed in 1943.

In 1942, months after the surprise attack on Peal Harbor, President Franklin D. Roosevelt ordered the internment and relocation of an estimated 120,000 people of Japanese descent. Though the Supreme Court upheld the constitutionality of these actions at the time – through Hirabayashi v. United States and Korematsu v. United States — they are largely seen today as a moment the country abandoned its principles.

President Obama speaks during an address to the nation from the Oval Office, December 6, 2015. (Photo: Saul Loeb/AFP)

A day before Trump unveiled his incendiary proposal, President Obama warned that betraying American values and discriminating against Muslims would play into the hands of terrorist groups like ISIS.

“It is our responsibility to reject religious tests on who we admit into this country,” Obama said in an address to the nation. “It’s our responsibility to reject proposals that Muslim-Americans should somehow be treated differently. Because when we travel down that road, we lose.”

The issue of Muslim immigration to the West has become particularly fraught in recent months because of two issues: the ongoing threat of jihadist groups and the Syrian refugee crisis.

The United States Holocaust Memorial Museum, sensitive to the consequences for Jews who could not flee the Third Reich in the 1930s and ’40s, released a statement last month urging others not to turn their backs on the thousands of refugees seeking safe haven outside war-torn Syria.

“The museum calls on public figures and citizens to avoid condemning today’s refugees as a group,” the statement reads. “It is important to remember that many are fleeing because they have been targeted by the Assad regime and ISIS for persecution and in some cases elimination on the basis of their identity.”

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