Writing for the Court, Chief Justice Salmon Chase ordered the case be dismissed for lack of jurisdiction. Chase began by establishing that while the Court’s appellate jurisdiction is derived from the Constitution, it’s conferred “with such exceptions and under such regulations as Congress shall make.” Therefore, when Congress enacts legislation that expressly removes jurisdiction over a certain class of cases, the Court is bound by that exception and can’t exercise power that Congress has withheld.

Chase clarified the limits of judicial inquiry into legislative acts, asserting that the Court wasn’t at liberty to question Congress’ motives for repealing the act, even if the timing suggested a political reason to block the Court from ruling on Reconstruction. Chase focused solely on Congress’ constitutional power to make exceptions to appellate jurisdiction, which he found to be clear and express in this case. However, Chase noted that the 1868 Act only repealed the specific jurisdiction conferred by the 1867 Act, explicitly stating that it didn’t affect the appellate power the Court possessed prior to that statute, therefore leaving open other potential avenues for habeas relief.

Chase rejected the argument that the repeal of the 1867 Habeas Corpus Act shouldn’t apply to McCardle’s pending case simply because it had already been argued. He reasoned that jurisdiction is fundamentally the “power to declare the law,” and when that power ceases to exist, the only remaining function for the Court is to announce the lack of jurisdiction and dismiss the cause. He explained that the Act of 1868 didn’t merely stay the proceedings but expressly repealed the statutory provision that McCardle’s appeal relied on, leaving the Court with no legal footing to render a judgment.