They cite "anonymous sources" for this information, and it begs the question of why, if others working for the court knew of this, it didn't come out before the decision?

What CBS is basically saying is that it was outside pressure on Roberts that caused him to pull the most consequential switcheroo in court history:

Over the next six weeks, as Roberts began to craft the decision striking down the mandate, the external pressure began to grow. Roberts almost certainly was aware of it.

Some of the conservatives, such as Justice Clarence Thomas, deliberately avoid news articles on the Court when issues are pending (and avoid some publications altogether, such as The New York Times). They've explained that they don't want to be influenced by outside opinion or feel pressure from outlets that are perceived as liberal.

But Roberts pays attention to media coverage. As Chief Justice, he is keenly aware of his leadership role on the Court, and he also is sensitive to how the Court is perceived by the public.

There were countless news articles in May warning of damage to the Court - and to Roberts' reputation - if the Court were to strike down the mandate. Leading politicians, including the President himself, had expressed confidence the mandate would be upheld.

[...]

It is not known why Roberts changed his view on the mandate and decided to uphold the law. At least one conservative justice tried to get him to explain it, but was unsatisfied with the response, according to a source with knowledge of the conversation.

Some informed observers outside the Court flatly reject the idea that Roberts buckled to liberal pressure, or was stared down by the President. They instead believe that Roberts realized the historical consequences of a ruling striking down the landmark health care law. There was no doctrinal background for the Court to fall back on - nothing in prior Supreme Court cases - to say the individual mandate crossed a constitutional line.

The case raised entirely new issues of power. Never before had Congress tried to force Americans to buy a private product; as a result, never before had the Court ruled Congress lacked that power. It was completely uncharted waters.

This has always concerned me about this case: Why is it "judicial activism" to uphold the principles of the Constitution -- even if, as in this case -- the legislation could be upheld based on precedent alone? Conservatives were arguing not for activism, but for restraint on the government. If the Court had a liberal majority, you can bet that the commerce clause would have been used to justify upholding the mandate. This is the very definition of "judicial activism" in that the Court would have vastly expanded the definition of "commerce" just to uphold the law.

It is Congress that overreached, and the Court's job -- as most of us see it -- was to rein in that power and define the limit of that power as it related to the commere clause. Setting limits on power is not activism, it is the primary job of the Court.

The dissent tried to make this point and why Roberts went from agreeing with it to siding with those who want to expand the power of government at the expense of the individual was apparently not a matter of law or the Constitution, but a matter of politics.

We better face facts; judges (with few exceptions), whether they identify with the right or the left, have an institutional bias against setting limits on the power of government to coerce and control our lives. Liberal justices seek pretexts to expand government power and will brook no limits on it in search of their mythical idea of "social justice." Conservative justices like Roberts (and the bulk of his decisions to date would indicate that he is, indeed, a conservative judge), may not agree in this expansive view of government power, but are nevertheless constrained to fight it because their idea of restraint is twisted by the dominant liberal media and elites into something it isn't; "conservative activism."

Is it any wonder we don't have limits on government power?