As a candidate, Donald Trump notoriously called for a ban on the entrance of all Muslims, a database to track Muslims in the United States, for aggressive surveillance of “the mosques,” and for closing down mosques. When many pointed out that such religiously targeted enforcement actions would be unconstitutional, he began talking instead about “extreme vetting” – apparently not getting that what the Constitution forbids is selective targeting of a religious group, regardless of the type of burden imposed. Now that he’s President-elect, his transition team is reportedly discussing requiring immigrants from Muslim-majority countries to register with the immigration authorities. Reince Priebus said on “Meet the Press” Sunday that “we’re not going to have a registry based on a religion.” But this is semantics; the transition team is reportedly planning just that, only under the guise of focusing on countries that happen to be majority Muslim. Kansas Secretary of State Kris Kobach, a virulently anti-immigrant hard-liner who introduced a similar registration scheme when he worked for President George W. Bush, is now working with the Trump transition, and told Reuters that the team was discussing reviving the registration scheme, which President Obama had ended in 2011. Kobach maintained that because the program he was discussing would be focused not on religion, but on countries that have a terrorist presence, the scheme would survive constitutional challenges. But there’s a huge difference between what Bush did and what Trump is proposing. Bush’s scheme had a disparate effect on Muslims, but there was no evidence that Bush himself had adopted it to target Muslims. Trump, by contrast, has left a long trail of smoking guns making clear his anti-Muslim intent. 

When executive action is challenged as targeting religion, the critical question is intent: If the government can be shown to have intentionally targeted a religious group, its actions violate the Free Exercise Clause. The law need not name the religion by name. It is enough to show that an anti-religious intent was at play. As with race or sex discrimination, if the government takes action that appears neutral on its face but was adopted for the purpose of singling out a racial minority, it is subject to stringent scrutiny and virtually always invalid.

"When executive action is challenged as targeting religion, the critical question is intent: If the government can be shown to have intentionally targeted a religious group, its actions violate the Free Exercise Clause."

In Church of Lukumi Babalu Aye v. City of Hialeah, for example, the Supreme Court in 1993 struck down a local Florida ordinance banning animal sacrifice because it found that the laws were triggered by animus against the Santeria religion, an Afro-Cuban sect that had recently moved into Hialeah and practiced animal sacrifice. The law did not mention Santeria on its face, but the surrounding circumstances made it clear that its intent was to single out that religion.

Of course, it is often difficult to prove improper intent. Even where they might be acting for impermissible purposes, the architects of a program rarely admit it outright. As a result, the Supreme Court has ruled that circumstantial evidence can support a finding of unconstitutional intent – things like the history of the act, its impact, the sequence leading up to its adoption, any unusual departures from business as usual, etc.

So what’s the evidence on Trump? It’s almost too numerous to detail, but here’s a sampler.

• On December 7, 2015, the Trump campaign issued a press release stating that “Donald J. Trump is calling for a total and complete shutdown of Muslims entering the United States until our country’s representatives can figure out what is going on.”
• In July 2016, he effectively admitted that his revamping of the proposal was designed to target Muslims without expressly saying so. In an interview on “Meet the Press: with NBC’s Chuck Todd,” Trump said he would target immigrants from certain countries, but resisted the suggestion that this was a retreat from his proposal to target Muslims. “I actually don’t think it’s a rollback. In fact, you could say it’s an expansion… People were so upset when I used the word Muslim. Oh, you can’t use the word Muslim. Remember this. And I’m OK with that, because I’m talking territory instead of Muslim.”
• In November 2015, Trump told NBC News he “would certainly implement” a database to track Muslims in the United States … “I would certainly implement that. Absolutely.” Would Muslims be legally required to register? “They have to be — they have to be,” Trump replied.
• In March 2016, Trump said, “Frankly, look, we’re having problems with the Muslims, and we’re having problems with Muslims coming into the country.”

The Trump team has even sought to defend its proposed plan to target Muslims by citing the Japanese internment of World War II (which in itself is another admission that the registry is not simply based on geography but religion and descent). In November, Carl Higbie, a spokesman for the pro-Trump Great American PAC, argued that a registry of immigrants from Muslim countries would pass constitutional muster, citing the internment of Japanese-Americans during World War II. But Korematsu v. United States, the case that upheld the Japanese internment, is more an anti-precedent than a precedent. As of 9/11, every justice on the Supreme Court except David Souter was on record condemning the decision. Congress ultimately issued a formal apology for the wrong and paid reparations. When Trump supporters have to resort to citing a decision like Korematsu, it only underscores how dubious their proposals really are.

Others, including law professors Eric Posner and Eugene Volokh, have argued that the “plenary power” doctrine would permit an immigration measure targeted at Muslims. To be clear, Posner and Volokh think such a proposal would be “stupid and offensive,” and “a very bad idea,” respectively, but not unconstitutional. In their view, “plenary power” trumps all, so to speak. But theirs is a vast overreading of the doctrine, which grants the political branches broad discretion over who may enter the United States. It is true that in the 19^th century the Supreme Court cited “plenary power” to permit the exclusion of Chinese immigrants, and that the doctrine has often been cited to exclude foreigners based on nationality and political associations. But while the power over immigration is broad, the Court has also insisted, in Carlson v. Landon, that “this power is, of course, subject to judicial intervention under the ‘paramount law of the constitution.’” The plenary power is not a blank check. And of course, surveilling and closing mosques is not an exercise of immigration authority, and would directly burden the rights of citizens.

What is more, the fact that the Court has been lenient with respect to nationality distinctions in immigration law governing admission does not mean it would tolerate religious distinctions even at the border. It is difficult to imagine how one might regulate immigration without making nationality-based distinctions, and our immigration laws have long drawn such lines. We have different visa rules for immigrants and visitors from different countries, and we not infrequently adopt country-specific immigration rules to address particular problems, such as a refugee crisis in a particular country. So making distinctions on the basis of nationality is intrinsic to immigration. But it is another thing entirely to use the immigration power to target people of a specific religion. We have no history of doing so and no legal precedent allowing it. There is simply no reason why religion should be relevant to immigration.

Moreover, under the Establishment Clause, which protects all of us from government actions favoring or disfavoring particular religions, the government is precluded from taking actions that make people of a particular religion feel that they are outsiders, especially once they are in the country. This is why it is unconstitutional, for example, for a city to display a Christian cross; it makes those who are not Christian feel excluded. If citizens have a constitutional right to object to the mere display of a cross because of the message it sends, surely they have at least as strong a right to object to a policy that treats Muslim human beings as suspect based on nothing more than their religious identity.

It’s true that President Bush’s special registration program, targeted at 25 majority-Muslim countries and North Korea, withstood constitutional challenge. (The courts relied on the history of drawing distinctions based on nationality cited above). Special registration was eventually scrapped not because courts declared it unconstitutional but because DHS itself found that it was a counterproductive waste of resources: it generated no terrorist convictions and caused widespread resentment in the very communities with which law enforcement sought to work to identify potential terrorists.

But under President Bush, there was no smoking gun evidence that the program was intentionally targeted at Muslims. It had that effect, but effect alone is rarely alone to demonstrate intent. With Trump, by contrast the evidence of anti-Muslim intent is overwhelming. Imagine that as a candidate, Trump had announced plans to ban the admission of blacks, create a national database of blacks, and investigate black churches, and then, upon election, instituted a registration requirement for immigrants from African countries. Would anyone doubt that his action was based on racial animus? Trump’s targeting of Muslims is just as blatant—and just as unconstitutional.