Empirical evidence of Roberts’ switch in the ACA case

The metrics suggest Roberts was not the only one to switch

With a Supreme Court nominee declaring there has been a left-wing conspiracy against him, naturally people are wondering whether a Justice Kavanaugh, if confirmed, could eventually act in a more judicious fashion. If not, might the new median of Court, Chief Justice Roberts, rise to the challenge of putting the institutional interests of the Court above his own political preferences? Looking back at the Chief’s role in deciding the fate of the Affordable Care Act (aka Obamacare), we are optimistic that he can.

When the fate of the ACA was decided in NFIB v. Sebelius, many were surprised to see the conservative Chief side with the liberal justices to uphold the signature legislation of the Democrat President. Others anticipated it, expecting Roberts to subvert his political preferences to avoid a 5:4 conservative-liberal divide on such a salient case in the lead-up to the 2012 election. On reading the opinions, many were struck by the fact that Roberts’ majority opinion read in large part as a manifesto against the legislation he was unhappily upholding; in addition, the dissent at times referred to the majority as “the dissent.” This suggested that Roberts may have initially sided with the conservatives – a view furthered by rumors to that effect. Until now, this has all been speculation. Here, we assess the empirical evidence from oral argument as to whether Roberts switched, and find some interesting results: not only did Roberts switch, but he was not the only one who changed his vote on some of the issues.

The four separate parts to the Obamacare oral argument

There were four questions addressed in four separate oral arguments over three days: (1) whether the constitutional validity of the ACA should even be heard by the Court; (2) whether Congress has power to require Americans to purchase healthcare, via the individual mandate, either under the Commerce Clause or the Taxing and Spending Clause; (3) whether, if the individual mandate was unconstitutional, it was severable, or alternatively, if the rest of the ACA must fall as a result; (4) and whether Congress exceeded its powers under the Spending Clause by threatening to withhold Medicaid spending to non-cooperating states. The following figures show how the justices behaved at each of the four oral arguments in order, measured by the disagreement gap. As we explained in more detail in a previous post, the justices tend to have more to say to the side they ultimately vote against. This can be measured in terms of speech events or just the difference in the number of words. If the gap is very small, we treat it as a weak signal, colored gray; occasionally, the size of the disagreement gap on one measure will be large but other factors, such as the balance of statements versus questions, or the disagreement gap on another measure, indicates that the signal should be treated as weak.

ACA Issue 1 Disagreement Gap (Words) [Click on the image to expand]

ACA Issue 1 Disagreement Gap (Speech Events) [Click on the image to expand]
On the first issue, of whether the Court should address the substantive issues at all in light of the Anti-Injunction Act, the above figure shows that at least four of the justices strongly indicated a desire to decide the case on its merits, and the others did not give a clear signal. Only Justice Scalia seemed consistently against a decision on the merits, but only with a weak signal from a justice who seldom held his cards close to his chest. The first issue, then, looked cross-partisan, with Justices Sotomayor and Kagan wanting to hear the case, presumably to uphold the legislation, as clearly as Justice Alito, who presumably wanted to strike down the legislation. Roberts, too, made clear his desire to decide the case on the merits. Consistent with this, the Court ultimately unanimously held that the Anti-Injunction Act did not apply and that the case should be decided on the merits. This suggests that our metrics are working reasonably well.

ACA Issue 2 Disagreement Gap (Words) [Click on the image to expand]
ACA Issue 2 Disagreement Gap (Speech Events) [Click on the image to expand]
The second issue was the key question in the case and here our analysis in the figure above strongly suggests that Roberts did indeed switch his vote from striking down the legislation to upholding it under the Taxing Power. On both measures, the disagreement gap in words and speech episodes, Roberts consistently measures as the second most vehement against the ACA, behind Alito on one measure and Scalia on another. At oral argument, Roberts seemed to be the most consistently opposed to the ACA and yet he ultimately provided the swing vote in favor.

However, it is important to note that this oral argument addressed the government’s power to pass the ACA under both the Taxing Clause and the Commerce Clause. In authoring the majority opinion, although Roberts found the ACA constitutional under the Taxing Clause, he went out of his way to make clear that the Commerce Clause did not support the passage of the ACA. If Roberts had gone into the oral argument thinking that the ACA was valid as a tax but not under the Commerce Clause, we would have expected to see at least mixed signals from him during this section of oral argument rather than a signal strongly against the ACA. Furthermore, given that if the law was valid as a tax, its status under any other head of constitutional power should have been irrelevant, if Roberts held his tax position from the outset, he should have been less interested in the Commerce Clause issue.

ACA Issue 3 Disagreement Gap (Words) [Click on the image to expand]
ACA Issue 3 Disagreement Gap (Speech Events) [Click on the image to expand]
So it looks like Roberts switched his vote on the all-important second issue, but he was not alone in making a switch on an issue in this case. On the third issue, as seen in the above figure, Justices Kagan, Breyer, and Sotomayor all come out very strongly on both measures in favor of severability, pointing to a way that even if the mandate was struck down, the rest of the Act would stand. Yet, eventually all three of those justices joined the 5:4 majority that did not answer this question, even though the dissent addressed the issue in detail. This is not surprising: compromise is a standard part of the political and diplomatic process of building a coalition on a multi-judge court. What is noteworthy is that it shows that Roberts was not the only one who appeared to have switched – our empirical analysis of the oral argument suggest that other Justices were also acting strategically in NFIB v. Sebelius.

ACA Issue 4 Disagreement Gap (Words) [Click on the image to expand]
ACA Issue 4 Disagreement Gap (Speech Events) [Click on the image to expand]
Given Justice Thomas’ habitual silence, oral argument on the fourth issue indicated a very clear 4:4 liberal-conservative divide among the speaking justices would translate into a conservative 5:4 ruling. Such an ideological division would have fit with previous Spending Clause decisions (e.g. New York v. United States, 1992). Yet, the ultimate outcome was 7:2 against the ACA. At oral argument, Justices Kagan and Breyer led the pro-ACA charge when it came to the disagreement gap in speech events and both were close behind Sotomayor in terms of the disagreement gap in the number of words, and ahead of Justice Ginsburg. And yet Kagan and Breyer joined the opinion striking down this part of the ACA. The majority decision looks to be a product of politics: perhaps Kagan and Breyer were making a strategic concession – compromising on the Spending issue to ensure the constitutionality of the legislation under the Taxing power – or perhaps they were following the Chief’s lead and moderating their positions to preserve the institutional legitimacy of the Court.

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Our empirical analysis of the oral argument in NFIB v. Sebelius indicates that four justices ultimately voted against at least one of their priors on display at oral argument. It is, of course, possible that our metrics are inaccurate, but they align with many commentators’ and experts’ expectations at the time. Possibly, these justices changed their fundamental views some time after oral argument, but another explanation is more likely. We see NFIB v. Sebelius as a case study in judicial strategy, the politics of compromise and coalition building, and how the justices occasionally sacrifice their individual policy preferences to protect the legitimacy of the Court.

By Tonja Jacobi and Matthew Sag

Notes: (1) Thanks to Barry Weingast for suggesting this inquiry. (2) For a more detailed account, see Tonja Jacobi, Obamacare As A Window on Judicial Strategy, 80 Tenn. L. Rev. 763 (2013) (ssrn link)