Opinion Summary: Mullin v. Al Otro Lado | The Inch That Changed Immigration Law

Mullin, Secretary of Homeland Security, et al. v. Al Otro Lado, et al. | Case No. 25-5 | Docket Link: https://www.supremecourt.gov/search.aspx?filename=/docket/docketfiles/html/public/25-5.html | Argued: March 24, 2026 | Decided: June 25, 2026

Overview: Border-access challenge determining whether federal immigration law requires officers to inspect and process asylum seekers at ports of entry before they cross into U.S. territory, or whether statutory duties attach only upon physical territorial entry.

Question Presented: Whether noncitizens blocked at the border before physically crossing "arrive in the United States," triggering mandatory inspection and asylum-processing duties under federal immigration law.

Posture: Ninth Circuit affirmed district court; district court declared metering policy unlawful; Supreme Court reversed.

Main Arguments:

• Government (Petitioner): (1) "Arrives in" carries its ordinary meaning — physical territorial entry; a running back stopped at the 1-yard line has not arrived in the end zone; (2) INA inspection and removal procedures presuppose U.S. presence — officers cannot enforce them against people standing in Mexico; (3) Sale v. Haitian Centers Council and the presumption against extraterritoriality confirm statutory duties apply only inside U.S. territory.
• Asylum Seekers (Respondent): (1) "Arrives in" covers noncitizens in the process of arriving at ports — otherwise the clause wholly duplicates "physically present," violating the surplusage canon; (2) Congress enacted §§1158 and 1225 to implement non-refoulement obligations barring return of refugees to persecution; (3) Federal regulations for 30 years defined "arriving alien" as anyone "attempting to come into the United States at a port-of-entry."

Holding: An alien standing in Mexico does not "arrive in the United States" by attempting and failing to cross the border. The INA neither entitles such an alien to apply for asylum nor requires an immigration officer to inspect them.

Voting Breakdown: 6-3. Justice Alito wrote the majority opinion, joined by Chief Justice Roberts and Justices Thomas, Gorsuch, Kavanaugh, and Barrett. Justice Thomas filed a concurring opinion. Justice Sotomayor filed a dissenting opinion, joined by Justices Kagan and Jackson. Justice Jackson filed a separate dissenting opinion. Reversed and remanded. 138 F.4th 1102, reversed and remanded.

Majority Reasoning: (1) "Arrives in" carries its ordinary meaning — entering within the limits of a place — not merely approaching its threshold; dictionary definitions and everyday analogies confirm physical entry controls; (2) Other INA provisions expressly cover those who "attempt to enter," but §§1158 and 1225 omit attempt language — Congress acted deliberately; (3) Presumption against extraterritoriality bars reading these statutes to reach people standing on Mexican soil.

Separate Opinions:

• Justice Thomas — Concurring: Joined majority fully. Wrote separately to flag two future issues: §1252(f)(1) may bar class-wide declaratory relief in immigration cases; and compelling the President to admit specific aliens would raise serious constitutional questions about inherent executive exclusion authority.
• Justice Sotomayor — Dissenting (joined by Justices Kagan and Jackson): "Arrives in" covers noncitizens in the process of arriving at ports; federal regulations, the anti-surplusage canon, and the present-tense statutory language all demand inspection duties attach before physical crossing. Majority's ruling will cost lives.
• Justice Jackson — Dissenting: DHS rescinded metering in 2021 with no concrete reinstatement plans; the case approached mootness and the Court effectively issued an advisory opinion in a factual vacuum. Also joined Sotomayor dissent on the merits.

Implications: (1) Government can resume metering; asylum and inspection duties attach only after a noncitizen physically crosses the border; (2) Future APA challenges to specific metering policies — applied as subterfuge when ports retain capacity — remain live; (3) Thomas's concurrence signals future challenges to class-wide immigration court orders and expanded presidential exclusion authority.

The Fine Print:

• 8 U.S.C. §1225(a)(1): "An alien present in the United States who has not been admitted or who arrives in the United States (whether or not at a designated port of arrival...) shall be deemed for purposes of this chapter an applicant for admission."
• 8 U.S.C. §1158(a)(1): "Any alien who is physically present in the United States or who arrives in the United States (whether or not at a designated port of arrival...), irrespective of such alien's status, may apply for asylum in accordance with this section or, where applicable, section 1225(b) of this title."

Primary Cases:

• Sale v. Haitian Centers Council, Inc. (1993): Article 33 of the Refugee Convention cannot restrict U.S. actions toward aliens outside U.S. territory; statutory refugee protections apply only within the United States.
• Morrison v. National Australia Bank Ltd. (2010): Courts presume federal statutes apply domestically unless Congress affirmatively and unmistakably directs extraterritorial reach.

Oral Advocates:

• Petitioners (Noem, et al.): Vivek Suri, Assistant to the Solicitor General, Department of Justice
• Respondents (Al Otro Lado): Kelsi B. Corkran of the the of Institute for Constitutional Advocacy and Protectio