The Washington Post says the Supreme Court's mistake requires it to reconsider the ban on the death penalty for rape of a child.

It's absolutely right:

The majority determined that capital punishment for child rape was unconstitutional, in part because a national consensus had formed against it. As evidence, the court noted that "37 jurisdictions -- 36 States plus the Federal Government -- have the death penalty. [But] only six of those jurisdictions authorize the death penalty for rape of a child." Actually, only two years ago, Congress enacted a death penalty for soldiers who commit child rape, as part of an update to the Uniform Code of Military Justice (UCMJ). Irony of ironies: The court has cast doubt on the constitutionality of an act of Congress based on the erroneous claim that the statute did not exist....

The Supreme Court's legitimacy depends not only on the substance of its rulings but also on the quality of its deliberations. That's why we think the court needs to reopen this case -- even though we supported its decision. The losing party, Louisiana, still has time to seek a rehearing, which the court could grant with the approval of five justices, including at least one from the majority. The court could limit reargument to briefs on the significance of the UCMJ provision. We doubt the case will come out much differently; we certainly hope not. But this is an opportunity for the court to show a little judicial humility. Before the court declares its final view on national opinion about the death penalty, it should accurately assess the view of the national legislature.

The opinion doesn't cohere as written. The dissenting opinion doesn't cohere. It's an egregious mistake that throws all the reasoning out of whack. Fix it!

ADDED: Has the Supreme Court case ever used the expression "out of whack"? No. The word "whack" only appears once in the Supreme Court's cases, in a one-sentence rejection of jurisdition in a case called Whack v. Maryland, 450 U.S. 990 (1981).

Is it "out of whack" or "out of wack"? If you go by Google hits, you'll think it's "out of wack" — but that's "out of whack." "Wack" means crazy. It's a back-formation from "wacky." As a noun, it means "a person regarded as eccentric." "Whack," as a noun, is a "a sharp, swift blow." I know, it makes little sense to say the reasoning is out of a person regarded as eccentric or out of a sharp, swift blow, but trust me, the standard, idiomatic expression is "out of whack."

Here's some history:

At one time, [whack] could mean a share in a distribution, a portion; this sense was originally thieves’ cant — Francis Grose, in his Dictionary of the Vulgar Tongue of 1785, has “Whack, a share of a booty obtained by fraud” (could physical violence have been involved in some cases?). British English has a couple of phrases that retain that sense. One is pay one’s whack, to pay one’s agreed contribution to shared expenses. Another is top whack, or full whack, for the maximum price or rate for something (“if you go to that shop, you’ll pay top whack”).

There are some other old figurative senses, including a bargain or agreement (which evolved out of the idea of a share), and an attempt at doing something (“I’ll take a whack at that job”). These are mostly American, and it was in the US that the sense you refer to first appeared, in the latter part of the nineteenth century. There seems to have been a phrase in fine whack during that century, meaning that something was in good condition or excellent fettle. (It appears in a letter by John Hay, President Lincoln’s amanuensis, dated August 1863, which describes the President: “The Tycoon is in fine whack. I have rarely seen him more serene and busy. He is managing this war, the draft, foreign relations, and planning a reconstruction of the Union, all at once”.) It doesn’t often turn up in writing, though, so there’s some doubt how widespread it was.

To be out of whack would then have meant the opposite — that something wasn’t on top form or working well.