Jonathan Ernst / Reuters

In mid-June of a typical year, Supreme Court justices and their clerks are burning the midnight oil in the comforting knowledge that soon all involved will be happily winging off to vacation destinations, leaving controversy temporarily behind.

That happy prospect is complicated this year, however, by the June 1 arrival in the Court’s in-box of Trump v. International Refugee Assistance Program, the East Coast-based challenge to what President Trump himself adamantly insists on calling his “travel ban” on entry of persons from six majority-Muslim countries. The Court almost certainly will have to decide before leaving town whether to hear the case (hint: it will) and if so, when.

Justices contemplating this case may feel that they are staring into a labyrinth of potential missteps and institutional dangers. On Monday, their fellow judges from the Ninth Circuit Court of Appeals threw them a map of an escape route, if they care to take it.

The Ninth Circuit’s decision came in Hawaii v. Trump, a different challenge to the travel ban. In this version of the case, a Hawaii district court enjoined the order because, the judge said, it violates the Establishment and Equal Protection Clauses.  Both cases potentially pose a set of novel and important questions. First, to what extent are a president’s national-security decisions limited by those two clauses of the Constitution? Second, when if ever should a reviewing court use a presidential candidate’s campaign statements, and a sitting president’s speeches and tweets, to interpret the “purpose” of an executive order?

Reading the executive mind in this case seems almost laughably easy—candidate Trump, among other things, discussed a story about a general shooting Muslims with bullets dipped in pig’s blood, then vowed to “shut down” admission of Muslim immigrants; after his inauguration, tweeter-in-chief Trump reaffirmed that, whatever his lawyers say, his executive order is a “travel ban.” But easy cases often make bad law: A decision to heed the tweets may embroil future courts in more difficult cases, and blur the line between executive discretion and judicial review. An opinion applying the religion and equal-protection clauses to immigration decisions—even ones as blatantly bigoted as this one—could also stir up unpredictable questions down the road.

The Ninth Circuit’s opinion neatly dodged these tricky questions. The court expressed no opinion on the constitutional issues, and made almost no mention of speeches and tweets. Instead, it simply decided that Trump’s ban is unlawful because, in promulgating it, he did not follow the procedures and rules of the Immigration and Nationality Act. (In addition, it narrowed the district court’s order by telling the administration it is free to begin its internal study of “extreme vetting,” on the chance that someday it will be put into effect.)

The court expressed this perfectly ordinary administrative-law judgment in an unsigned “per curiam” opinion—a designation usually applied to unanimous decisions that don’t address any novel or interesting issues. Nothing to see here, the Ninth Circuit seemed to be saying. (As an added benefit, because no single judge signed the order, perhaps no single judge will be subject, as District Judge Derrick Watson was, to death threats requiring round-the-clock protection.)

First, the panel wrote, the Immigration and Nationality Act provides procedures for a president to follow in limiting immigration; Trump ignored those procedures and thus his order is invalid. Second, the statutes Trump cites in the ban actually don’t give him the substantive authority to discriminate in entry by nationality. Thus the vexing issues of religious discrimination, and of Trump’s “true” intent, don’t arise.

Trump and his lawyers have relied heavily on one immigration statute, 8 U.S.C. 1182(f), as authorization for the ban:

Whenever the President finds that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States, he may by proclamation, and for such period as he shall deem necessary, suspend the entry of all aliens or any class of aliens as immigrants or nonimmigrants, or impose on the entry of aliens any restrictions he may deem to be appropriate.

This seems like a fairly sweeping grant of power. But the Ninth Circuit panel concluded (as Judge Barbara Keenan of the Fourth Circuit did in a separate opinion in the  earlier case) that the order contains “no sufficient finding … that the entry of the excluded classes would be detrimental to the interests of the United States.”

To non-lawyers, this may seem like wordplay; but in administrative law, the difference between statements and “findings” can be important. Courts often invalidate major executive programs because administrative procedures, like not making factual findings or holding hearings, have not been followed. For example, consider President Barack Obama’s “deferred action” program for certain undocumented aliens. The district court that blocked that program did so because it concluded that administrative law rules required Obama to permit public comment before beginning the program. The court of appeals affirmed on the grounds that the statute didn’t allow the program at all. Neither court reached any constitutional issue.

In the travel ban case, the Ninth Circuit panel in effect combined both approaches, procedure and substance. Procedurally, Trump’s order “makes no finding that nationality alone renders entry of this broad class of individuals a heightened security risk to the United States” and does not “provide a rationale explaining why permitting entry of nationals from the six designated countries under current protocols would be detrimental to the interests of the United States.”

Nor did the order make a “finding” that the refugee program, created by statute, posed “any threat or harm to warrant suspension” of refugee admissions. Though the government argued that national-security determinations should not be second-guessed, the panel said, “National security is not a ‘talismanic incantation’ that, once invoked, can support any and all exercise of executive power under § 1182(f).”

As to discrimination: Trump’s ban on admission of nationals from the six countries appears to violate a different part of the immigration code, § 1152(a)(1)(A). This section provides that, with a few exceptions, “no person shall receive any preference or priority or be discriminated against in the issuance of an immigrant visa because of the person's race, sex, nationality, place of birth, or place of residence.” That statute was enacted years after 1182(f); thus, the panel argued, should be read as a limit on it. Discriminating by nationality was not justified by the statute.

The panel also rejected the administration’s strongest precedent, Kleindienst v. Mandel. That 1972 decision approved the attorney general’s refusal to waive immigration rules for a distinguished Marxist academic who wanted to visit the U.S. for a conference. Mandel states that when an executive immigration decision is “facially legitimate and bona fide,” the court’s will not “look behind” it to find illicit motive. But Mandel doesn’t apply, the Ninth Circuit panel argued, because in that case the executive was clearly authorized to apply a specific rule set by Congress—exclude advocates of revolutionary Marxism—and the challenger was demanding an exception to the rule. Here there is no such specific statutory rule, and courts needn’t defer.

If your eyes are starting to glaze, that probably means that the Ninth Circuit’s opinion is having the desired effect. Not addressed in the opinion are “establishment of religion” or “equal protection of the laws.” Not mentioned are what the Fourth Circuit called “religious intolerance, animus, and discrimination.” Absent are inflammatory quotations from campaign speeches and presidential statements. (The sole exception is one of Trump’s recent tweets explaining that the order was aimed at “DANGEROUS countries”; but that tweet is quoted to establish discrimination by country, which Trump has never denied.)

Donald Trump seems to many—surely including some of the justices—to come before the Court as a rogue president seeking its blessing to trample on the law and Constitution, and threatening “slow and political” courts and “so-called judges” who get in his way. Ruling against him may seem like the right thing to do, but explaining why may not seem easy.

The Ninth Circuit offers a way out: If the statutes didn’t authorize the order, then, well, no need to go into all that other unpleasantness, is there?

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