By Haiyun Damon-Feng*
One of the cruelest and most devastating Trump-era immigration policies was the Remain in Mexico policy, formally titled the “Migrant Protection Protocols” (MPP). MPP upended decades of established asylum law and practice, forcing asylum seekers to wait in Mexico pursuant to a bilateral agreement between the U.S. and Mexico—where many were kidnapped, raped, tortured, or otherwise exploited or killed for their vulnerability as migrants—while they pursued their immigration cases before U.S. immigration courts. The Biden administration issued a memorandum terminating MPP in June 2021, but two months later, Judge Matthew Kacsmaryk of the U.S. District Court for the Northern District of Texas ordered the administration to “enforce and implement MPP” in a nationwide injunction issued in Texas v. Biden. In so ordering, Judge Kacsmaryk broke with long-standing precedent cautioning judicial deference to the political branches in matters implicating foreign affairs and seemed to subordinate the Executive’s interest in controlling such matters to States’ interests in immigration enforcement. This essay is not a normative argument in defense of deference, but rather an account of how the District Court in Texas boldly—and without discussion or acknowledgment—did away with such deference in ordering the Biden administration to re-start MPP, and how the Supreme Court, in refusing to stay the injunction, seemed not to mind.
I. MPP Likely Violates the Immigration and Nationality Act
MPP has stood on questionable legal footing since its inception. The Trump administration implemented MPP by utilizing the “contiguous territory return” provision in Section 235(b)(2)(C) of the Immigration and Nationality Act (“INA”) in a way that it had never been used before. Structurally, the INA provides that asylum seekers who arrive in the U.S. without documentation may be placed into summary proceedings called expedited removal proceedings, and that “other aliens” arriving from a contiguous territory may be returned to such territory pending full removal proceedings. Under MPP, however, the Department of Homeland Security (“DHS”) sought to effectively transform individuals in the “arriving asylum seekers” category into the “other aliens” category and subject them to the contiguous territory return provision in violation of the INA.
On February 28, 2020, the Ninth Circuit issued an order enjoining MPP in Innovation Law Lab v. Mayorkas, holding that MPP was inconsistent with the INA. However, that injunction was stayed by the Supreme Court pending appeal, and MPP was allowed to continue through to the end of the Trump administration. Ultimately, some 71,000 people were returned to Mexico under MPP before the program was terminated by President Biden.
On January 20, 2021, President Biden suspended MPP, and DHS terminated the policy on June 1, 2021. During the initial wind-down of MPP, over 10,000 asylum seekers were paroled and processed into the U.S. All of that came to an abrupt halt following a nationwide injunction issued in Texas v. Biden by the U.S. District Court for the Northern District of Texas.
II. History and Foreign Affairs Backdrop Behind MPP
An important point to note is that MPP returns non-Mexican asylum seekers present in the United States to wait in Mexico for the pendency of their U.S. immigration proceedings. As such, MPP would not be possible without Mexico’s agreement to accept such non-Mexican nationals. MPP was initially negotiated and agreed to by the Trump administration and then-incoming Mexican President Lopez Obrador’s administration in November 2018, and the program was first implemented in January 2019.
In the spring of 2019, then-President Trump tweeted a series of threats toward Mexico, threatening to close the border and implement tariffs on Mexican goods unless Mexico did more to stop the flow of asylum seekers into the United States. On May 31, the Mexican government reportedly went into “diplomatic overdrive…to head off punishing tariffs threatened by the Trump administration in retaliation for the rising number of migrants reaching the U.S. border.” Ultimately, Mexico was able to avoid tariffs by agreeing to “an unprecedented crackdown on Central American migrants and accepting more-expansive measures in Mexico if the initial efforts don’t deliver quick results.” The measures included, among other things, the agreement to expand Mexico’s acceptance of returns of asylum seekers under MPP, despite Mexico reportedly wanting to resist U.S. pressure to increase the number of people it accepted through the program.
III. Texas and Missouri Sue Over the Termination of MPP
MPP has always been a hot-button political issue. On the campaign trail, then-candidate Biden was critical of MPP and reaffirmed that he would end MPP during his transition. Just two weeks before Biden’s inauguration and in an apparent effort to stave off the impending immigration policy changes—including the termination of MPP—the outgoing Trump administration entered into a Memorandum of Understanding (“MOU”) with the State of Texas, pledging to “prioritize detention over release of inadmissible and removable aliens” and promising to consult with Texas prior to “in any way modifying” then-existing immigration enforcement policies or procedures. The MOU further stated that any failure to meet such obligations would cause irreparable harm to the aggrieved party, setting the stage for Texas to challenge any Biden-era policy that would modify or terminate MPP (or any other Trump-era immigration policy).
Seizing on the opportunity provided to it by the MOU, Texas filed suit, along with the State of Missouri, against the Biden administration seeking to stop the wind-down and termination of MPP. That case, Texas v. Biden, was decided on August 13, 2021, when Judge Matthew Kacsmaryk issued a nationwide injunction ordering the Biden administration to “enforce and implement MPP in good faith until such a time as it has been lawfully rescinded in compliance with the APA and until such a time as the federal government has sufficient detention capacity to detain all aliens subject to mandatory detention under Section 1255 without releasing any aliens because of a lack of detention resources.” The Department of Justice filed a notice of appeal three days later and sought to stay the injunction pending such appeal. The request for stay was denied by the Fifth Circuit and then by the Supreme Court in a summary order off the Court’s “shadow docket.”
IV. District Court’s Departure from Foreign Affairs Deference
The District Court’s order in Texas is problematic, both factually and legally, but this essay focuses on the fact that the District Court’s opinion breaks with long-standing precedent cautioning judicial restraint and deference to the political branches in matters relating to foreign affairs. Curiously, Judge Kacsmaryk does not engage at all with the law on this point. Instead, he flippantly dismisses the administration’s concerns that such an order would disrupt delicate bilateral and multilateral agreements as a “self-inflicted” “inconvenience.” He further dismisses the administration’sconcerns that the Court’s injunction would “create doubt about the reliability of the United States as a negotiating partner” and “be damaging to our national and economic security,” by responding that, “Mexico is capable of understanding” the reasons for such an order. In so doing, Judge Kacsmaryk appears to elevate States’ interests in immigration enforcement above the Executive Branch’s interests in controlling and regulating foreign affairs, raising federalism and separation of powers concerns that the Court of Appeals and Supreme Court were presented with, but did not address, in their decisions denying a stay.
The history of immigration law in this country, for better or worse, has generally been a story of judicial deference to the political branches. Beginning with Chinese Exclusion in the late 1800s, courts have recognized the plenary power of the political branches to regulate immigration and have generally refused to review immigration policy for what might otherwise be constitutional violations. Over the years, courts have been more willing to scrutinize certain policies—but still, and particularly with respect to policies regulating immigration law and policy at the border—the plenary power persists. One leading theory on why this is rests upon the Court’s broader refusal to insert itself into matters of foreign relations.
Indeed, judicial deference to the political branches in matters of foreign relations extends beyond the immigration context, as courts frequently disavow themselves as suitable arbiters of such matters. In U.S. v. Curtiss-Wright Exporting Corp., the Supreme Court held that the ability to regulate foreign relations was inherent in sovereignty and suggested a sort of Presidential primacy over that realm. Scholars have long debated whether and how the foreign affairs power is split between Congress and the President, but there is generally no part of the foreign affairs power that has been reserved by or delegated to the Judiciary. In Chicago and Southern Air Lines v. Waterman S.S. Corp., the Supreme Court warned that foreign policy decisions “are decisions of a kind for which the Judiciary has neither aptitude, facilities nor responsibility and have long been held to belong in the domain of political power not subject to judicial intrusion or inquiry.”
Judicial intervention in foreign affairs is a separation of powers issue, a prudential issue, and a federalism issue. In the Chinese Exclusion Case, the Court explicitly stated that foreign affairs were not within the domain of the states, and that “[w]hile under our constitution and form of government the great mass of local matters is controlled by local authorities, the United States, in their relation to foreign countries and their subjects or citizens, are one nation.” Immigration and foreign affairs, separately and together, are distinctively federal issues that are not for States to regulate. In a more recent example from 2012, when Arizona passed S.B. 1070 in an apparent attempt to implement its own system of immigration regulation and enforcement, the Supreme Court again recognized the federal government’s sovereign power to regulate immigration and foreign relations and found certain provisions of the Arizona law to be preempted by federal immigration law. In Arizona v. U.S., the Supreme Court, citing to the Federalist Papers, observed that the“federal power [to determine immigration policy] would be necessary in part because ‘bordering States … under the impulse of sudden irritation, and a quick sense of apparent interest or injury’ might take action that would undermine foreign relations.”
This essay is not a normative defense of deference. Instead, it offers a critique of the District Court’s wholesale failure to engage with this line of precedent and the Supreme Court’s apparent willingness to go along with it. Just one year earlier, the Supreme Court, in a 8–1 vote, decided the other way and voted to stay the Ninth Circuit’s injunction of MPP after the Ninth Circuit found that the program was likely unlawful. Another striking example of the disconnect in the Judiciary’s treatment of Texas v. Biden lies in its comparison with the Supreme Court’s decision in Trump v. Hawaii. There, the Supreme Court again emphasized the principle that “judicial inquiry into the national security realm raises concerns for the separation of powers by intruding on the President’s constitutional responsibilities in the area of foreign affairs,” and it did so in order to uphold then-President Trump’s travel ban affecting primarily majority-Muslim countries. The Court, in a 5–4 decision with Justices Breyer, Kagan, Sotomayor and Ginsburg dissenting, refused to consider the overwhelming evidence of religious animus underlying the ban—also in the name of Presidential primacy over immigration and foreign relations. In the three years since Trump v. Hawaii was decided, Justice Ginsburg passed away and was replaced by Justice Barrett, and in Biden v. Texas, the Supreme Court refused to stay the District Court’s decision despite its flagrant encroachment on Presidential control over foreign affairs. This time, the vote was 6–3, again with Justices Breyer, Kagan, and Sotomayor dissenting.
V. Compliance with Court Order and Balancing Humanitarian Concerns
For now, the Biden administration is left to figure out how it can comply with the District Court’s order. Secretary Mayorkas has stated that DHS is “planning to implement the program while [they] litigate the ruling.” While it is not clear what that means specifically, the effects of the ruling have already been devastating.
Following the Supreme Court’s denial of a stay in Texas, DHS suspended the processing of people who were previously enrolled in MPP, leaving thousands of vulnerable asylum seekers who had been eligible for relief stranded in Mexico. I have been working with one such family through my work with the Adelante Pro Bono Project. Anna and her two daughters, one of whom suffers from chronic heart and kidney disease, were placed into MPP. They were ordered removed in absentia after failing to attend their hearing because they were kidnapped and held hostage while traveling through Mexico on their way to immigration court. The family came to the U.S. fleeing persecution and torture by government and military officials in Venezuela. After Anna participated in political activity and protests against the Maduro administration, the Venezuelan National Guard and armed defenders of Maduro’s party pelted her with rocks, tied her up and beat her, killed her dog, and threatened to rape her and her daughters if she continued to support the opposition. Because of MPP, Anna and her children were deprived of the opportunity to make their claim for asylum in court. Prior to the injunction, the family was on the brink of finally leaving the years-long nightmare they’ve endured under MPP. After the injunction, Anna gave up. On September 1, 2021, Anna made the impossible decision to return to Venezuela with her daughters because their situation is extremely dangerous and unsustainable in Mexico, and the indefinite wait proved to be too much.
Anna’s situation is not unique. Contrary to the District Court’s assertions that MPP is “effective” because its harsh conditions weed out unmeritorious claims, numerous people with meritorious asylum claims were ordered removed in absentia because they were kidnapped. Many others abandoned their meritorious claims because of the insurmountable and inhumane obstacles posed by MPP. Notably, although the District Court was presented with copious evidence detailing the human cost of MPP, these well-documented humanitarian concerns were nowhere mentioned in the District Court’s opinion (or the Fifth Circuit’s, or the Supreme Court’s). Instead, the discussion of harm focused solely on costs incurred by Texas (and Missouri and other States) that may arise from the termination of MPP.
So, what can the Biden administration do? The Biden administration can and should, of course, issue a new memo terminating MPP that accords with the APA and the District Court’s order. In the meantime, it can also take measures to mitigate the harm resulting from the injunction. One tool still at DHS’ disposal is its parole power under INA Section 212(d)(5), which gives the Secretary wide discretion to grant individuals parole for urgent humanitarian reasons or significant public benefit. The Fifth Circuit, in its decision denying a stay in Texas v. Biden, explicitly recognized that DHS retained its power to grant humanitarian parole, notwithstanding the District Court’s order. The Biden administration had been using humanitarian parole to process people previously enrolled in MPP into the U.S., and it can, and should, continue to do so. The administration could also suspend MPP to new enrollments pending further agency review and decision-making, similar to how the Trump administration suspended new enrollments in DACA while it reviewed the policy following the Supreme Court’s decision in DHS v. Regents of the University of California. And the administration could seek a legislative solution and clarification from Congress as to the statutory authority for a program like MPP, which remains a critical issue that has been—and will continue to be—subject to ongoing debate. Any resolution on this point, however, must also take into serious account the United States’ non-refoulement obligation not to return people to territories where their life or freedom would be threatened, which is enshrined in both international and federal law.
The Biden administration should make every effort not to re-enroll people in MPP or reopen MPP courts. However, if people are going to be re-enrolled in MPP, the Biden administration should develop a more robust non-refoulement screening process to ensure that people are not returned to places where they are vulnerable to violence, persecution, or torture, and should make meaningful use of exemptions to exclude vulnerable people from enrollment in MPP. Regardless of how the Biden administration chooses to proceed, it should not take action that would prolong or exacerbate the worsening humanitarian crisis at our southern border. It should remain committed to terminating MPP and to reopening removal orders previously issued under MPP in consideration of the egregious due process concerns endemic to MPP and the humanitarian crisis it has left in its wake, even if these concerns were overlooked by the courts in Texas v. Biden.
*Director, Adelante Pro Bono Project; Assistant Director, W.H. Gates Public Service Law Program, University of Washington School of Law. Many thanks to Christine Cimini, Catherine Kim, Jennifer Koh, and Taylor Levy for their thoughtful comments and insights, and to Catherine Walker-Jacks, the editors of the Harvard Law & Policy Review, and Cindy Fester for their helpful feedback and assistance.
 In a prior essay for the Harvard Law & Policy Review, I provided additional background on the humanitarian cost of MPP and argued that MPP must be both terminated and remedied to restore meaningful access to asylum.
 Innovation Law Lab v. Wolf, 951 F.3d 1073, 1083-85 (9th Cir. 2020) (“Under a plain-meaning reading of the text, as well as the Government’s longstanding and consistent practice, the statutory authority upon which the Government now relies simply does not exist.”), vacated as moot by Innovation Law Lab v. Mayorkas, 5 F.4th 1099 (Mem) (9th Cir. 2021).
 The Ninth Circuit held that the “contiguous territory return provision” under Section 1225(b)(2) of the INA (which was the provision relied upon by the Government as statutory authority for MPP) did not allow for the return of noncitizens described under Section 1225(b)(1), which includes noncitizens present in the U.S. without documentation but who intend to seek asylum. The Ninth Circuit further held that MPP likely violates the United States’ treaty- and statute-based non-refoulement obligations, which prohibit the United States from returning an individual to a territory where they are likely to be persecuted or tortured. The court found that people returned to Mexico pursuant to MPP “face targeted discrimination, physical violence, sexual assault, overwhelmed and corrupt law enforcement, lack of food and shelter, and practical obstacles to participation in court proceedings in the United States.”
 The Ninth Circuit’s decision was later vacated as moot after the Biden administration terminated the program.
 Under the INA, DHS generally retains authority to release individuals otherwise subject to detention, and it has routinely exercised this discretion for numerous reasons, including limitations on detention resources and space. INA §212(d)(5); §236(a). See also infra n. 13.
 The MOU was discussed at length by both the District Court and the Fifth Circuit. Ultimately, the District Court decided the matter on Administrative Procedure Act (“APA”) and statutory grounds and found Texas’ breach of contract claims arising from the MOU to be moot, but the Fifth Circuit nevertheless cited to the MOU in support of Texas’ APA claims. The Fifth Circuit found the MOU to be evidence of Texas’ reliance interests in MPP, that DHS “must consider” Texas’ interests in MPP because of the MOU, and that DHS’ failure to discuss the MOU in its memo terminating MPP “alone likely renders the Secretary’s decision arbitrary and capricious.” Texas v. Biden, 2021 WL 3674780 at *9–10 (5th Cir. 2021) (citing Regents of the University of California v. Dep’t of Homeland Sec’y, 140 S. Ct. 1891, 1913 (2020) (internal quotations omitted)).
 The District Court found that DHS’ termination of MPP was “arbitrary and capricious” under the APA because the memorandum terminating MPP failed to provide sufficient agency rationale and failed to consider factors such as Texas’ (and other states’) reliance interests in the ongoing implementation of MPP. The Supreme Court’s summary order denying a stay found that the Government “failed to show a likelihood of success on the claim that the memorandum rescinding the Migrant Protection Protocols was not arbitrary and capricious,” citing Regents.
 It bears noting that the District Court relies heavily on its conclusion that a) the INA requires mandatory detention of all asylum seekers, and b) that the INA is set up in a way such as to force a binary choice between mandatory detention and return to a contiguous territory, such as through a program like MPP. Neither of these is accurate. First, the INA provides that DHS generally retains discretion to parole or release an individual into the United States. INA 212(d)(5); INA 236(a). Second, the Ninth Circuit previously held that MPP violated the statutory scheme of the INA. In so doing, the Ninth Circuit cited both the legislative intent and structure of Section 235 of the INA (which contains the contiguous territoryreturn provision) and concluded that the contiguous territory return provision was not intended to apply to bona fide asylum seekers. Innovation Law Lab v. Wolf, 951 F.3d 1073 (9th Cir. 2020). That decision was on appeal before the Supreme Court and was vacated as moot following the Biden administration’s termination of MPP. See supra n. 2-6 and accompanying text.
 Chae Chan Ping v. U.S. (the “Chinese Exclusion Case”), 130 U.S. 581, 607 (1889); Dep’t of Homeland Sec’y v. Thuraissigiam, 140 S. Ct. 1959, 1982 (2020). See generally Stephen H. Legomsky, Immigration Law and the Principle of Plenary Congressional Power, 1984 S. Ct. Rev. 255 (1984).
 A recent example of courts reverting to the plenary power doctrine is from Thuraissigiam, supra note 16, where the Supreme Court held that the Due Process Clause did not apply to an individual in expedited removal proceedings apprehended 25 yards inside the U.S. border. Thuraissigiam,supra n. 16, at 1982. See also David A. Martin, Why Immigration’s Plenary Power Doctrine Endures, 68 Okla. L. Rev. 29, 32 (2015). Some scholars have argued that the plenary power has given way over the years due to the Court’s increasing willingness to adopt a more expansive view of fundamental constitutional rights generally. See, e.g., Peter H. Schuck, The Transformation of Immigration Law, 84 Colum. L. Rev. 4 and Hiroshi Motomura, Immigration Law After a Century of Plenary Power: Phantom Constitutional Norms and Statutory Interpretation, 100 Yale L.J. 545, 564 (1990). Others have attributed the retreat from plenary power in certain areas of immigration regulation to general concerns about delegation prevalent in increased oversight over the administrative state more broadly. Catherine Kim, Plenary Power in the Modern Administrative State, 96 N.C.L. Rev. 77, 83 (2017).
 Martin, Why Immigration’s Plenary Power Endures, supra n. 17, at 41; United States ex rel. Knauff v. Shaugnessy, 338 U.S. 537, 542 (1950) (“The exclusion of aliens is a fundamental act of sovereignty. The right to do so stems not alone from the legislative power but is inherent in the executive power to control the foreign affairs of the nation.”).
 Although not the focus of this essay, the courts’ treatment of MPP, taken both individually and in comparison with the treatment of other immigration policies, suggests a certain degree of partisan decision-making that is focused on the content and outcome of the immigration policy at issue in determining which immigration policies are enjoined, invalidated, stayed or upheld.
 I provide additional examples and further discussion on this point in a prior essay.
 As narrowed by the Fifth Circuit, which interpreted the District Court’s order on detention only to require that DHS not “simply release every [individual potentially subject to MPP] en masse into the United States.” Texas v. Biden, supra n. 9, at *14.
 The use of humanitarian parole in this context is not without precedent. Presidents throughout history have made good use of the humanitarian parole provision to address urgent humanitarian crises around the globe.
 Similar to the District Court’s opinion in Texas v. Biden, the Supreme Court in Regents held that the Trump administration’s termination of DACA violated the APA. The Supreme Court and Fifth Circuit cited to Regents heavily in their respective decisions not to stay the District Court injunction. However, in Texas, unlike in Regents, the policy at issue bears serious foreign affairs implications, and neither the Fifth Circuit nor the Supreme Court engaged in a discussion as to why this departure from the longstanding doctrine of judicial restraint was appropriate here.
 Another policy contributing to the crisis at the border is a Trump-era policy known as “Title 42,” which has been extended by the Biden administration with certain modifications. Title 42 began out of an order issued under the CDC’s emergency powers and effectively closes the border to asylum seekers, citing COVID concerns that public health experts have denounced as pretextual. The policy has resulted in migrants being kidnapped, assaulted, and killed; to families being separated; and to vulnerable asylum seekers being unlawfully denied access to humanitarian protection. To date, there have been over 1 million expulsions under Title 42.