The Supreme Court has decided to hear two legal challenges to President Donald Trump’s revised “travel ban.”

Among other things, the executive order Trump signed in March temporarily bars entry of nationals from six predominantly Muslim countries: Iran, Libya, Somalia, Sudan, Syria and Yemen.

In cases arising out of Maryland and Hawaii, lower courts had blocked applying the ban to all nationals from the six countries. Now, under the Supreme Court’s June 26 order, family members, students, employees and others with “a bona fide relationship with a person or entity in the United States” will be allowed entry. At the same time, the Supreme Court will allow part of the travel ban to go back into effect for “foreign nationals abroad who have no connection to the United States at all.”

The Supreme Court will hear the combined cases in October after the justices return from summer recess. Its decision will be its first major encounter with a president who criticizes the courts as political. As a professor of constitutional law who studies law and politics, I see four ways forward for the Supreme Court in these cases.

Two ways to strike down the travel ban

1. The Maryland case was brought by U.S. residents who are separated from family members in the six named countries. It challenges the travel ban as an unconstitutional “establishment of religion” under the First Amendment. In earlier cases, the Supreme Court has said the Establishment Clause “forbids an official purpose to disapprove of a particular religion…” Because the travel ban singles out six countries with overwhelmingly Muslim populations, the lower court held a “reasonable observer would likely conclude” the travel ban is intended to discriminate against Muslims. In doing so, it relied on Trump’s controversial statement during the campaign 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.” A decision on these grounds would require the Supreme Court to question the president’s motives – a highly unusual move.

2. The second case was brought by the state of Hawaii on behalf of its state university and a United States citizen whose Syrian mother-in-law seeks to immigrate. They claim the travel ban exceeds the president’s authority under immigration law. The travel ban relies on a 1952 law authorizing the president to “suspend the entry of all aliens or any class of aliens” if he finds their entry “would be detrimental to the interests of the United States.” Congress reformed immigration law in 1965 to prohibit discrimination on the basis of nationality in issuing visas, the documents allowing immigrants to enter the United States. The court held that the president did not show entry of people from the six countries “would be detrimental” under the 1952 law, and that the travel ban discriminated on the basis of nationality under the 1965 law. A decision on these grounds would leave the issue with Congress, which could then keep or change the law.

Two ways to leave the law as it stands

3. Traditionally, the Supreme Court has been reluctant to second-guess the president’s policy judgments involving national security. In earlier challenges, the Supreme Court has upheld the exclusion of individual foreign nationals, even where constitutional rights may be at stake, if the government offers a “legitimate and bona fide reason.” Under this broad language, vague concerns about terrorism could be a good enough reason. As the Supreme Court recognized in granting review of the cases, “preserving national security is an urgent objective of the highest order.” In a separate opinion accompanying the order, three of the Supreme Court’s conservative justices, including Trump appointee Justice Neil Gorsuch, suggested this factor should weigh heavily in favor of upholding the travel ban in its entirety.

4. The court’s order holds another clue about how it might decide the case. It asks the parties to brief the court on whether the challenges to the travel ban “became moot” or, or legally meaningless, when the 90-day travel ban ended, according to its original terms. That period is intended to give the government time to review its “vetting” of foreign nationals seeking entry into the United States. Once the government completes its review, the travel ban loses its original justification. The president recently moved back the 90-day clock to start when it takes limited effect after the Supreme Court’s order. Yet mootness remains a possibility. Even the extended timeline will end before the case is argued in October. If the case is moot, the Supreme Court would dismiss it without reaching a decision on the legality of the ban.

Win, lose or draw

It can be tempting to score these outcomes as either “wins” or “losses” for President Trump. However, the back-and-forth between the courts and the administration has already led to a significantly narrower revised ban after earlier cases struck down the original ban issued in January. Many people who would have been subject to both the original and revised travel bans now can enter the United States legally thanks to these cases.

This sometimes tense dialogue between the president and the courts is typical to the resolution of high-stakes legal controversies. For example, the government argued that the courts had no role to play in determining the rights of detainees at Guantanamo Bay after 9/11. Yet, the Supreme Court issued several decisions that prompted the president and Congress to revisit and temper detainee policies. In the last of these cases, Justice Anthony Kennedy on behalf of the Supreme Court encouraged the president and Congress to “engage in a genuine debate about how best to preserve constitutional values while protecting the Nation from terrorism.”

Whatever the fate of the travel ban, it is unlikely the Supreme Court will have the last word when it issues a decision this fall. Striking down the travel ban as unconstitutional would still allow for new restrictions on immigration. Upholding the travel ban would still allow for narrower challenges to the policy and its implementation. Holding the travel ban illegal under immigration law, or finding the case moot, would throw the issue back to the president and Congress. In each of these outcomes, look for the Supreme Court again to encourage “a genuine debate.”

Anthony Johnstone does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.