At pages 16-17 of the slip opinion, the Court says,

We know as well that common-law courts entertained habeas petitions brought by enemy aliens detained in England—“entertained” at least in the sense that the courts held hearings to determine the threshold question of entitlement to the writ. See Case of Three Spanish Sailors, 2 Black. W. 1324, 96 Eng. Rep. 775 (C. P. 1779); King v. Schiever, 2 Burr. 765, 97 Eng. Rep. 551 (K. B. 1759); Du Castro’s Case, Fort. 195, 92 Eng. Rep. 816 (K. B. 1697).

In Schiever and the Spanish Sailors’ case, the courts denied relief to the petitioners. Whether the holdings in these cases were jurisdictional or based upon the courts’ ruling that the petitioners were detained lawfully as prisoners of war is unclear. See Spanish Sailors, supra, at 1324, 96 Eng. Rep., at 776; Schiever, supra, at 766, 97 Eng. Rep., at 552. In Du Castro’s Case, the court granted relief, but that case is not analogous to petitioners’ because the prisoner there appears to have been detained in England. See Halliday & White 27, n. 72. To the extent these authorities suggest the common-law courts abstained altogether from matters involving prisoners of war, there was greater justification for doing so in the context of declared wars with other nation states. Judicial intervention might have complicated the military’s ability to negotiate exchange of prisoners with the enemy, a wartime practice well known to the Framers.

This is woefully inadequate. The Spanish sailors and probably DuCastro were temporary residents of Britain and its dominions and thus within the protection of its laws. The sailors were in service on a British flag vessel. DuCastro was apparently in England before his detention and likely a temporary resident there. See CJLF brief at 16-17.

This leaves Schiever as the case most closely analogous to the Guantanamo detainees. He had no prior connection to the country and no prior claim to the protection of its laws. He was captured by the military outside the boundaries of British control and held by the military as an enemy prisoner.

There are two published reports of Schiever's case by different reporters, both reproduced in the English Reports. The one cited in the Court's opinion is unclear whether the dismissal of the petition is on the merit or jurisdictional, as the Court says. The other is not.

He is the King’s prisoner of war, and we have nothing to do in that case, nor can we grant an habeas corpus to remove prisoners of war. His being a native of a nation not at war does not alter the case, for by that rule many French prisoners might be set at liberty, as they have regiments of many other kingdoms in their service, as Germans, Italians, &c.

But, if the case be as this man represents it, he will be discharged upon application to a Secretary of State.

Schiever's Case, 96 Eng. Rep. 1249 (K.B. 1759).

There is nothing remotely "unclear" about this. This is clear as crystal. This is as clear as it gets. The court expressly said his claim had merit if his allegations were true, but the court could not give him relief, and he had to look to the executive.

Schiever is a single case, to be sure, but its force is strengthened by the absence of a single contrary example. The Halliday and White article is based on an extensive search of records and was written with the Guantanamo litigation in mind, yet it does not cite a single example of habeas relief for a military prisoner in these circumstances.

If the Court had simply overlooked this in the flood of amicus briefs filed in this case, it would at least be understandable. However, this point was expressly mentioned by the Solicitor General at oral argument, page 71. The Court was certainly aware of it.

The majority's glossing over of this point is disappointing, to put it mildly. Why the dissent did not nail them on it is even more puzzling. And, of course, whether there was greater "justification" for the rule in some kinds of wars than others is utterly irrelevant to the constitutional question. If prisoners in these circumstances were not holders of the "Privilege of the Writ of Habeas Corpus" at common law, the privilege written into the Constitution, then the decision of whether and under what circumstance to extend that privilege to them belongs to the legislative branch, not the judiciary.