Yesterday, the Supreme Court released its opinion in Shady Grove v. Allstate.

On the whole, the issue was quite simple:

New York law prohibits class actions in suits seeking penalties or statutory minimum damages. We consider whether this precludes a federal district court sitting in diversity from entertaining a class action under Federal Rule of Civil Procedure 23.

The answer was no: 

The question in dispute is whether Shady Grove’s suit may proceed as a class action. Rule 23 provides an answer. It states that “[a] class action may be maintained” if two conditions are met: The suit must satisfy the criteria set forth in subdivision (a) (i.e., numerosity, commonality, typicality, and adequacy of representation), and it alsomust fit into one of the three categories described in subdivision (b). Fed. Rule Civ. Proc. 23(b). By its terms this creates a categorical rule entitling a plaintiff whose suit meets the specified criteria to pursue his claim as a class action. (The Federal Rules regularly use “may” to confer categorical permission, see, e.g., Fed. Rules Civ. Proc. 8(d)(2)–(3), 14(a)(1), 18(a)–(b), 20(a)(1)–(2), 27(a)(1),30(a)(1), as do federal statutes that establish procedural entitlements, see, e.g., 29 U. S. C. §626(c)(1); 42 U. S. C. §2000e–5(f)(1).) Thus, Rule 23 provides a one-size-fits-all formula for deciding the class-action question. Because §901(b) attempts to answer the same question—i.e., it states that Shady Grove’s suit “may not be maintained as a class action” (emphasis added) because of the relief it seeks—it cannot apply in diversity suits […] .

In short, States cannot preclude state-law class actions from being filed in federal court because the federal rules specifically permit class actions.

The way in which the Supreme Court got there, however, was anything but simple:

SCALIA, J., announced the judgment of the Court and delivered the opinion of the Court with respect to Parts I and II–A, in which ROBERTS, C. J., and STEVENS, THOMAS, and SOTOMAYOR, JJ., joined, an opinion with respect to Parts II–B and II–D, in which ROBERTS, C. J., and THOMAS, and SOTOMAYOR, JJ., joined, and an opinion with respect to Part II–C, in which ROBERTS, C. J., and, THOMAS, J., joined. STEVENS, J., filed an opinion concurring in part and concurring in the judgment. GINSBURG, J., filed a dissenting opinion, in which KENNEDY, BREYER, and ALITO, JJ., joined.

Yikes.

Let’s break that down.

Scalia wrote an opinion that was broken up into Parts I, II-A, II-B, II-C, and II-D.

Five justices agreed with Parts I and II-A: Scalia, Roberts, Stevens, Thomas and Sotomayor. Those two parts are thus the law of the land.

Four justices agreed with Parts II-B and II-D: Scalia, Roberts, Thomas and Sotomayor.

Three justices agreed with Part II-C: Scalia, Roberts and Thomas.

Stevens, in addition to joining Parts I and II-A, wrote a separate concurrence.

Ginsburg disagreed with all of it, so wrote a dissent, with which Kennedy, Breyer and Alito agreed.

Here’s the interesting part. Stevens agreed with the result and with Parts I and II-A of Scalia’s opinion, but didn’t agree with the rest, so he wrote a concurrence explaining why he didn’t also join Parts II-B, II-C, and II-D.

Sotomayor, in contrast, agreed with Parts I, II-A, II-B, and II-D, but not with II-C. Let’s take a look at the beginning of Part II-C to figure out why not:

A few words in response to the concurrence. We understand it to accept the framework we apply—which requires first, determining whether the federal and state rules can be reconciled (because they answer different questions), and second, if they cannot, determining whether the Federal Rule runs afoul of §2072(b). Post, at 5–7 (STEVENS, J., concurring in part and concurring in judgment). The concurrence agrees with us that Rule 23and §901(b) conflict, post, at 15–16, and departs from usonly with respect to the second part of the test, i.e., whether application of the Federal Rule violates §2072(b), post, at 7–13. Like us, it answers no, but for a reason different from ours. Post, at 17–22.

The concurrence would decide this case on the basis, not that Rule 23 is procedural, but that the state law it displaces is procedural, in the sense that it does not “function as a part of the State’s definition of substantive rights and remedies.” Post, at 1. A state procedural rule is not preempted, according to the concurrence, so long as it is “so bound up with,” or “sufficiently intertwined with,” a substantive state-law right or remedy “that it defines the scope of that substantive right or remedy,” post, at 4, 13.

This analysis squarely conflicts with Sibbach, which established the rule we apply. […]

Presumably, since Sotomayor did not join Part II-C, she disagreed with its criticisms of Stevens’ concurrence.

Yet, she also didn’t join Stevens’ concurrence. She didn’t give any indication as to what she thought about the debate between Part II-C (i.e., Scalia, Roberts and Thomas) and Stevens’ concurrence.

Why not? We may never know.

You, however, are reading a blog, so let’s speculate.

As I wrote before about Sotomayor’s first opinion, in Mohawk Industries v. Carpenter, "As hoped, Justice Sotomayor has brought her trial experience to bear, and has contributed a practical understanding of how the law works at the trial level previously unseen in Supreme Court opinions."

My speculation is: Sotomayor understood that the debate between Scalia, Roberts, Thomas and Stevens was irrelevant to deciding the case at hand. The debate was, in legal terms, little more than dictum proprium that would serve only to confuse lower courts.

Every time a Supreme Court nomination comes up, politicians throw around the terms "judicial temperament" and "judicial restraint."

If you want to know what these terms mean, look no further than Justice Sotomayor.