"More or less constitutional"

In the opinion of the Court in the Affordable Care Act case, Chief Justice Roberts quotes approvingly his predecessor, Chief Justice Marshall: “The peculiar circumstances of the moment may render a measure more or less wise, but cannot render it more or less constitutional.”

The Court's job on questions of constitutionality, Roberts writes, is clear: "[T]here can be no question that it is the responsibility of this Court to enforce the limits on federal power by striking down acts of Congress that transgress those limits." And for Roberts, the approach the Court should take to such questions is categorical: is the statute in question within one of the "enumerated powers" granted to Congress by the Constitution; and, if so, is the statute nevertheless in conflict with the Bill of Rights.

That's the doctrinal method of operation. 

In point of practice, however, the justices do have tactical means that permit them to navigate foggy waters (gray areas). Roberts uses at least one such tool to hinge his swing vote upholding the controversial law.

Namely, Roberts invokes a principle of construction, dressed as an admonishment for judicial modesty, that, where a plausible alternative interpretation is available that would render a statute constitutional, a court should err on the side of finding constitutionality.

That's exactly what Roberts does here. In spite of finding that Congress had no power to pass the law under the Commerce Clause of the Constitution, he's willing to entertain fancy legal gymnastics that characterize the individual mandate provision of the Act as a "tax." Because the power to tax is one of the enumerated powers of Congress, the Act can be said to pass muster. In effect, the Affordable Care Act is "more or less constitutional."

You might say Roberts gets to have his cake and eat it, too. Not wanting to repeat the mistake of Chief Justice Tawney, he finds a way to uphold this highly politicized law, and at the same time signal that he and the conservative majority of the Court stand ready to further constrain legislative power under a narrowing construction of the Commerce Clause.

It's a fascinating high-wire act.

Moreover, the Chief Justice communicates all of this plainly and transparently, without the meanness or self-aggrandizement that often characterizes Justice Scalia's opinions. 

There is but one sentence in Justice Robert's opinion that might be mistaken as something Justice Scalia might say:

"It is not our job to protect the people from the consequences of their political choices."

But you have to take that sentence out of context to read it as mean. Roberts' prose - and in particular the first two pages, which lay out both Roberts' love for and understanding of the American system of federalism and how the fifty states and the Supreme Court fit into that system - evidences a respect for, and even a sense of accountability to, "the people."