Congress gives immigration judges discretionary power to cancel the removal of a noncitizen and instead permit the noncitizen to remain in the country lawfully. 8 U. S. C. §§1229b(a)–(b). An IJ faced with an application for cancellation of removal proceeds in two steps: The IJ must decide first whether the noncitizen is eligible for cancellation of removal under the statutory criteria. If the IJ finds the noncitizen statutorily eligible, the IJ must then decide whether to exercise discretion and grant relief. For determining eligibility, Congress has enumerated four statutory criteria, one of which requires the noncitizen to “establis[h] that removal would result in exceptional and extremely unusual hardship to [the noncitizen’s] spouse, parent, or child,” who is a U. S. citizen or lawful permanent resident. §1229b(b)(1)(D).

  Petitioner Situ Kamu Wilkinson was arrested and detained by Immigration and Customs Enforcement for remaining in the United States beyond the expiration of his tourist visa. Wilkinson applied for cancellation of removal based in part on hardship to his 7-year-old, U. S.-born son, M., who suffers from a serious medical condition and relies on Wilkinson for emotional and financial support. To meet the hardship standard, Wilkinson had to show that M. “would suffer hardship that is substantially different from or beyond that which would ordinarily be expected to result from [his] removal.” In re Monreal-Aguinaga, 23 I. & N. Dec. 56, 62. Considering all of the hardship factors presented by Wilkinson in the aggregate, the IJ held that M.’s situation did not meet the statutory standard for “exceptional and extremely unusual” hardship and denied Wilkinson’s application. The Board of Immigration Appeals affirmed. The Third Circuit held that it lacked the jurisdiction necessary to review the IJ’s discretionary hardship determination. This Court granted certiorari to determine whether the IJ’s “exceptional and extremely unusual” hardship determination is a mixed question of law and fact reviewable under §1252(a)(2)(D) or whether that determination is discretionary and therefore unreviewable under §1252(a)(2)(B)(i).

Held: The Third Circuit erred in holding that it lacked jurisdiction to review the IJ’s determination in this case. Pp. 7–16.

 (a) The Third Circuit held that it lacked jurisdiction on the basis of §1252(a)(2)(B)(i), which makes unreviewable any “judgment[s] regarding the granting of [discretionary] relief” under §1229b’s cancellation of removal provision. Section 1252(a)(2)(D), however, restores jurisdiction to review “questions of law.” The interaction between these two provisions is governed by two of this Court’s previous cases: Guerrero-Lasprilla v. Barr, 589 U. S. 221, and Patel v. Garland, 596 U. S. 328. In Guerrero-Lasprilla, the Fifth Circuit reasoned that whether a noncitizen acted diligently in attempting to reopen removal proceedings for purposes of equitable tolling was a question of fact, not a jurisdiction-restoring “questio[n] of law”. This Court reversed, holding that “questions of law” in §1252(a)(2)(D) included mixed questions of law and fact. 589 U. S., at 225. The Court rejected the Government’s argument that “questions of law” referred only to mixed questions that are primarily legal rather than primarily factual. Then, in Patel, this Court affirmed an Eleventh Circuit holding that it lacked jurisdiction to review an IJ’s factual credibility determinations that fell within §1252(a)(2)(B)(i)’s jurisdictional bar. In so doing, the Court held that §1252(a)(2)(D) did not restore jurisdiction in the case because “questions of fact” are indisputably not “questions of law.” Pp. 7–11.

 (b) Wilkinson argues that §1252(a)(2)(D) restores jurisdiction in this case because the threshold question whether a noncitizen is statutorily eligible for cancellation of removal requires a court to assess whether an IJ correctly applied the statutory standard to a given set of facts. Guerrero-Lasprilla compels the conclusion that the application of the statutory “exceptional and extremely unusual hardship” standard to a given set of facts presents a mixed question of law and fact. A mixed question may require “primarily legal or factual work,” and just because it may require a court to immerse itself in facts does not transform the question into one of fact. U. S. Bank N. A. v. Village at Lakeridge, LLC, 583 U. S. 387, 396.

 In this case, the application of the hardship standard—which requires an IJ to evaluate a number of factors in determining whether any hardship to a U. S. citizen or permanent-resident family member is substantially different from what would normally be expected in the removal of a close family member—concededly requires a close examination of the facts. As in Guerrero-Lasprilla, a mixed question that requires close engagement with the facts is still a mixed question, and therefore a “questio[n] of law” reviewable under §1252(a)(2)(D). And as in Patel, the IJ’s underlying factual determinations that Wilkinson was credible or that M. had a serious medical condition would be unreviewable factual questions under §1252(a)(2)(D). Pp. 11–12.

 (c) The Government’s counterarguments are unpersuasive. First, nothing in Guerrero-Lasprilla or this Court’s other precedents limits that case solely to judicially created standards like the “due diligence” standard for equitable tolling. And this Court has frequently observed that the application of a “statutory standard” presents a mixed question of law and fact. See, e.g., Pullman-Standard v. Swint, 456 U. S. 273, 289, n. 19. Second, the case of Williamsport Wire Rope Co. v. United States, 277 U. S. 551, on which the Government relies, has no relevance to the question presented here on §1252(a)(2)(D), and the Government provides no basis for porting the interpretation of “exceptional hardship” in that case to this one. Nor is the Government’s argument from the statutory history of the “hardship requirement” any more persuasive. Finally, the argument that a primarily factual mixed question is a question of fact was previously rejected in Guerrero-Lasprilla, and nothing in §1252(a)(2)(D) supports the Government’s view that the phrase “questions of law” is so limited. Pp. 12–15.

Reversed in part, vacated in part and remanded.

 Sotomayor, J., delivered the opinion of the Court, in which Kagan, Gorsuch, Kavanaugh, and Barrett, JJ., joined. Jackson, J., filed an opinion concurring in the judgment. Roberts, C. J., filed a dissenting opinion. Alito, J., filed a dissenting opinion in which Roberts, C. J., and Thomas, J., joined.

Respondent Yonas Fikre, a U. S. citizen and Sudanese emigree, brought suit alleging that the government placed him on the No Fly List unlawfully. In his complaint, Mr. Fikre alleged that he traveled from his home in Portland, Oregon to Sudan in 2009 to pursue business opportunities there. At a visit to the U. S. embassy, two FBI agents informed Mr. Fikre that he could not return to the United States because the government had placed him on the No Fly List. The agents questioned him extensively about the Portland mosque he attended, and they offered to take steps to remove him from the No Fly List if he agreed to become an FBI informant and to report on other members of his religious community. Mr. Fikre refused. He then traveled to the United Arab Emirates, where he alleges authorities interrogated and detained him for 106 days at the behest of the FBI. Unable to fly back to the United States, he ended up in Sweden, where he remained until February 2015. While there, he filed this suit, alleging that the government had violated his rights to procedural due process by failing to provide either meaningful notice of his addition to the No Fly List or any appropriate way to secure redress. He further alleged that the government had placed him on the list for constitutionally impermissible reasons related to his race, national origin, and religious beliefs. Mr. Fikre sought, among other things, an injunction prohibiting the government from keeping him on the No Fly List and a declaratory judgment confirming the government had violated his rights. In May 2016, the government notified Mr. Fikre that he had been removed from the No Fly List and sought dismissal of his suit in district court, arguing that its administrative action had rendered the case moot. The district court agreed with the government, but the Ninth Circuit reversed, holding that a party seeking to moot a case based on its own voluntary cessation of challenged conduct must show that the conduct cannot “reasonably be expected to recur.” 904 F. 3d 1033, 1039. On remand, the government submitted a declaration asserting that, based on the currently available information, Mr. Fikre would not be placed on the No Fly List in the future, and the district court again dismissed Mr. Fikre’s claim as moot. The Ninth Circuit once again reversed, holding that the government had failed to meet its burden because the declaration did not disclose the conduct that landed Mr. Fikre on the No Fly List and did not ensure that he would not be placed back on the list for engaging in the same or similar conduct in the future. 35 F. 4th 762, 770–772.

Held: The government has failed to demonstrate that this case is moot. A court with jurisdiction has a “virtually unflagging obligation” to hear and resolve questions properly before it. Colorado River Water Conservation Dist. v. United States, 424 U. S. 800, 817 (1976). But the converse is also true as a federal court must dismiss a case that is moot. Already, LLC v. Nike, Inc., 568 U. S. 85, 91 (2013). The limited authority vested in federal courts by Article III of the U. S. Constitution to decide cases and controversies means that federal courts may no more pronounce on past actions that have no “continuing effect” in the world than they may neglect their obligation to hear and resolve questions properly before them. Spencer v. Kemna, 523 U. S. 1, 18. This does not imply that a defendant may “automatically moot a case” by the simple expedient of suspending its challenged conduct after it is sued. Instead, a defendant’s “voluntary cessation of a challenged practice” will moot a case only if the defendant can show that the practice cannot “reasonably be expected to recur.” Friends of the Earth, Inc. v. Laidlaw Environmental Services (TOC), Inc., 528 U. S. 167, 189. This standard holds for governmental defendants no less than for private ones. Applying these principles to the uncontested factual allegations here, this case is not moot. While the government’s representation that it will not relist Mr. Fikre may mean that his past conduct is not enough to warrant relisting, that does not speak to whether the government might relist him if he engages in the same or similar conduct in the future. The government contends that because Mr. Fikre has been delisted since 2016 and has presumably interacted freely with his co-religionists during that time, it is unlikely he will face relisting in the future. This too is insufficient to warrant dismissal. A defendant’s speculation about a plaintiff’s actions cannot make up for a lack of assurance about its own. The burden here is on the defendant to establish that it cannot reasonably be expected to resume its challenged conduct, see West Virginia v. EPA, 597 U. S. 697, 719, and nothing the government offers here satisfies that formidable standard. The government claims the Ninth Circuit erred by requiring it to repudiate its past conduct to prove mootness, but what matters is not whether a defendant repudiates its past actions, but what the defendant can prove about its future conduct. Coming as this case does in a preliminary posture, the Court’s judgment is a necessarily provisional one. As the complaint’s allegations are tested, different facts may emerge that may call for a different result. But adhering to traditional mootness principles, the government has so far failed to meet its burden. Pp. 5–10.

35 F. 4th 762, affirmed.

 Gorsuch, J., delivered the opinion for a unanimous Court. Alito, J., filed a concurring opinion, in which Kavanaugh, J., joined.