A few days ago I blogged about a question that some readers had asked: why hasn’t United States v. Arizona — the case in which the U.S. is challenging the constitutionality of Arizona’s law dealing with illegal immigrants — hasn’t been filed from the outset before the United States Supreme Court? Article III, section 2 of the Constitution provides, in relevant part (subclause numbers added),
The judicial Power shall extend  to all Cases, in Law and Equity, arising under this Constitution, the Laws of the United States, and Treaties made, or which shall be made, under their Authority;  –to all Cases affecting Ambassadors, other public Ministers and Consuls;  –to all Cases of admiralty and maritime Jurisdiction;  –to Controversies to which the United States shall be a Party;  –to Controversies between two or more States;  –between a State and Citizens of another State,  –between Citizens of different States,  –between Citizens of the same State claiming Lands under Grants of different States, and  between a State, or the Citizens thereof, and foreign States, Citizens or Subjects. [The Eleventh Amendment provided that  and  do not cover lawsuits against a state by a citizen of another state or a foreign citizen or subject. -EV]
In all Cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be Party, the supreme Court shall have original Jurisdiction. In all the other Cases before mentioned, the supreme Court shall have appellate Jurisdiction, both as to Law and Fact, with such Exceptions, and under such Regulations as the Congress shall make.
In U.S. v. Arizona, “a State [is] Party,” so why doesn’t “the supreme Court ... have original Jurisdiction” (without regard to any “Regulations as the Congess shall make,” since that latter clause is applicable only to “the other Cases before mentioned”)?
As I mentioned at the time, I am not an expert on the law of federal jurisdiction, so I couldn’t speak to this with great confidence. But I offered some analysis, which you can read here. Some of my commenters (and particularly Andrew), though, helped educate me on this. Now it seems to me that my analysis missed the likely correct answer, which the Court gave in Cohens v. Virginia, 19 U.S. 264, 396-402 (1821): Original jurisdiction extends only to cases brought under the jurisdictional bases provided in those subclauses that expressly mention Ambassadors and State Parties, which is to say , , , and . It does not extend to cases brought under other jurisdictional bases, such as cases arising under the federal Constitution or federal laws, that happen to have a State as a party.
So if a State sues another State, the Court does have original jurisdiction; likewise if a State sues a citizen of another State (though in that situation, the Court may also have appellate jurisdiction, as my original post discussed, and as Cohens also held). But if some entity other than a State sues the State under the federal Constitution or federal statutes, then the Court does not have original jurisdiction, since the basis of jurisdiction (here, ) is not one of those bases that stem from the defendant’s being a State. Here is how Cohens puts it:
In one description of cases [in the numbered clauses above -EV], the jurisdiction of the Court is founded entirely on the character of the parties, and the nature of the controversy is not contemplated by the constitution. The character of the parties is every thing, the nature of the case nothing. In the other description of cases, the jurisdiction is founded entirely on the character of the case, and the parties are not contemplated by the constitution. In these, the nature of the case is every thing, the character of the parties nothing. When, then, the constitution declares the jurisdiction, in cases where a State shall be a party, to be original, and in all cases arising under the constitution or a law, to be appellate — the conclusion seems irresistible, that its framers designed to include in the first class those cases in which jurisdiction is given, because a State is a party, and to include in the second, those in which jurisdiction is given, because the case arises under the constitution or a law.
It seems to me that the federal original jurisdiction statute, 28 U.S.C. § 1251, is not entirely consistent with its reasoning, because it provides, in subsection (b)(2), that “The Supreme Court shall have original but not exclusive jurisdiction of ... All controversies between the United States and a State.” Controversies between the United States and a State do not constitute one of the jurisdictional bases in article III, section 2, clause 1, so under the logic of Cohens (plus Marbury v. Madison, which held that Congress may not enlarge the Court’s original jurisdiction) the Court may not have original jurisdiction over them. Federal courts, including the Supreme Court, might have jurisdiction over them, usually because they involve questions arising under the federal Constitution or laws; but by the logic of Cohens, this could only be appellate jurisdiction. But Cohens does seem clear on this, and its interpretation of the Constitution would thus make § 1251(b)(2) unconstitutional. [UPDATE: Thanks to Prof. Tung Yin, who mentioned that United States v. Texas (1892) (pp. 642-46) held that original jurisdiction extends also to suits by the United States against the states.]
So this is my new, but still tentative, thinking on the matter. If I’m right on this, then Cohens means that the U.S. Supreme Court is constitutionally barred from having original jurisdiction over the United States v. Arizona lawsuit — federal trial court is a proper place for it to be, and then eventually it might get to the Supreme Court through the Court’s appellate jurisdiction. But again, please do correct me if I’m mistaken.