Senator Dianne Feinstein asked Judge Sotomayor about the federal government's Commerce Clause power today.

One question on the commerce clause in the Constitution. That clause, as you well know, is used to pass laws in a variety of contexts, from protecting schools from guns to highway safety to laws on violent crime, child pornography, laws to prevent discrimination and to protect the environment, to name just a few examples.

When I questioned now Chief Justice Roberts, I talked about how, for 60 years, the court did not strike down a single federal law for exceeding congressional power under the commerce clause.

In the last decade, however, the court has changed its interpretation of the commerce clause and struck down more than three dozen cases. My question to the chief justice and now to you is: do you agree with the direction the Supreme Court has moved in more narrowly, interpreting congressional authority to enact laws under the commerce clause?

Either Senator Feinstein misspoke, or she needs better staff. In the last decade, the Supreme Court has only struck down a single federal statute for exceeding the scope of the federal commerce clause power. In United States v. Morrison (2000), the Court invalidated portions of the Violence Against Women Act. Given her reference to "protecting schools," I assume she meant to include the Court's 1995 decision in United States v. Lopez, but that only increases the number of cases to two in which the Court found Congress exceeded the scope of its Commerce Clause power.

I've spent some time pondering what Senator Feinstein could have meant when she said the Supreme Court had "struck down more than three dozen cases" under the Commerce Clause. Adding up all of the cases in which the Court found statutes exceeded all of the federal government's enumerated powers, including the sovereign immunity cases, the commandeering cases, and the 14th Amendment cases, in the last twenty years still doesn't get us to the three-dozen-plus cases Feinstein claimed. Add in the federalism-related constitutional avoidance cases, and we're still a ways off.

Maybe she meant to include dormant commerce clause cases as well — I haven't counted those — but that would have been an odd choice both because a) dormant commerce clause cases limit state, rather than federal, power; b) Congress may overrule dormant commerce clause decisions, and c) there are reasons to suspect the Court is becoming less aggressive at policing the dormant commerce clause. So I don't think she meant to include these cases, and even if she had, I still don't think it would get us to 36 cases in the past ten years. What am I missing?

UPDATE: It appears Senator Feinstein may have been relying upon (and misquoting) Cass Sunstien's misleading 2005 Harper's article, "Fighting the Supreme Court," as this is the source of the claim that the Rehnquist Court struck down more than three-dozen federal statutes from 1995-2005. Yet less than a third of these were on federalism grounds — that is commerce clause and anti-commandeering and 14th Amendment and sovereign immunity (a point Sen. Feinstein has apparently noted in other contexts). In terms of the three-dozen federal statutes, this also includes statutes invalidated on grounds ranging from the First Amendment (such as federal measures aimed at porn on the internet) to the violation of bicameralism and presentment (the Line-Item Veto Act), and, if carried forward to the present, would include decisions like Boumediene. Yet including the full range of cases undercuts the "conservative judicial activism" meme articulated by Sunstein and echoed (inaccurately) by Sen. Feinstein.

UPDATE: Michael Dorf notes other Senators who seemed to have a problem accurately stating the law.