A Republican chief throwing out a Democratic president's legislative achievement would have further polarized the nation. For now, at least, we're only as polarized as we were before the decision. —Jon Meacham

A new CBS News report suggests that Chief Justice John Roberts switched his original position on President Barack Obama's health care overhaul, raising charges of politicization and pressure on the court.

The day after the ruling was announced, Sen. Mike Lee, R-Utah, a former clerk to Justice Sam Alito, told The Washington Examiner that there were signals within the dissent that one might see when a vote changed, but the CBS article took the suggestion mainstream. A new Salon article Tuesday said that Roberts wrote both the majority opinion and much of the dissent on the health care law, bolstering the possibility of a vote switch.

Theories quickly developed to explain why Roberts might have changed his position on the law.

Some have suggested that Roberts, who has often discussed the need to preserve the integrity of the bench, may have been swayed by outside influences. In April, Obama said overturning the law would be an "unprecedented, extraordinary step." In May, Sen. Patrick Leahy, D-Va., suggested from the Senate floor that voting against the health care law would be committing judicial activism. Other sources suggested impeaching the Supreme Court if it overturned the law, running against the court in the presidential election and rethinking the use of judicial review.

"As Roberts began to craft the decision striking down the mandate, the external pressure began to grow. Roberts almost certainly was aware of it," Jan Crawford wrote in her CBS report.

"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," Crawford said. "To strike down the mandate as exceeding the Commerce Clause, the court would have to craft a new theory, which could have opened it up to criticism that it reached out to declare the president's health care law unconstitutional. Roberts was willing to draw that line, but in a way that decided future cases, and not the massive health care case."

If the reported switch in opinion came due to political pressure, Roberts will have left a legacy that stains the court, an Investors Business Daily editorial said.

"If Roberts wanted to make the court look politically neutral, he failed miserably," the editorial said. "Nothing could be more political than the head of the bench rewriting bad law to avoid appearing political. If Roberts hoped to burnish the court's reputation, he succeeded only in staining it ... By all accounts, Roberts didn't play chess. He played politics, which is beyond outrageous."

"It is possible, of course, that Chief Justice Roberts simply thought about it and found the tax argument compelling enough to give Obamacare's mandate a pass," Peter Suderman wrote at Reason.com. "But given the report that he initially voted against the mandate and later went 'wobbly,' it also seems plausible that he switched his vote to uphold the mandate via the tax power not exclusively because he thought it the best and strongest legal argument, but with shaping the role and reputation of the court in mind."

The final 5-4 decision upholding the mandate occurred because Roberts "effectively redrafted the statute," making the mandate a tax in order to make it constitutional, Marc Thiessen wrote at The Washington Post, and it should be a lesson that new Supreme Court appointments must have the "the intestinal fortitude not to be swayed by pressure from The New York Times, the Georgetown cocktail circuit and the legal academy."

"If the assumption is right, that he thinks this was unconstitutional but found a way to uphold it to preserve the integrity of the court, then he really ought to resign because it proves that he doesn't have the judicial fortitude to do the job that he's been chosen to do," said John Eastman, a professor of law at Chapman University, during an interview on The O'Reilly Factor.

Some defended Roberts, saying that the move may have been political, but in a way that is consistent with the court's history and would protect the court's standing.

"In a nation still skeptical of a court that stopped the Florida recount in Bush v. Gore in 2000, Roberts decided to act in the Marshall-Warren tradition of protecting the court's standing by declining to exacerbate an already-tense political atmosphere," Jon Meacham wrote at Time. "A Republican chief throwing out a Democratic president's legislative achievement would have further polarized the nation. For now, at least, we're only as polarized as we were before the decision."

Matthew Franck at National Review cautioned Roberts' critics, saying that Roberts has a plausible case that can be defended on principled grounds when it comes to his opinion and that people ought to give Roberts some credit for doing his duty to the rule of law as he understands it.

The New Republic's Jeffrey Rosen wrote that Roberts' decision was an example of putting his oath above his own ideological agenda and that it was a "twistification" of which former Chief Justice John Marshall would be proud. Roberts upheld the individual mandate via taxing power but found the mandate unjustifiable under Congress's power to regulate interstate commerce, putting him in agreement with the four justices who wanted to overturn the mandate.

A Reuters post echoed this point, saying that Roberts' opinion in the health care case struck a blow for conservative constitutionalism while bolstering the court's moral authority and reminding the country of the difference between law and politics.

"Conservatives may be upset now, but over time they will come to appreciate that they gained far more than they lost from this decision," Michael McConnell suggested.

David Bernstein of the George Mason University School of Law authored at post at SCOTUSblog.com saying the decision showed that the five conservative justices were willing to put real, substantive limits to the scope of the commerce power, and that seven justices also endorsed substantive limits on the spending power.

"My point is simply that despite the Obama administration's victory today, we may be on the cusp of a new and unpredictable era in conservative jurisprudence," Bernstein wrote. "Liberal pundits were sure that the commerce clause challenge to the individual mandate would lose 8-1, and that the spending clause challenge to Medicaid expansion was even more frivolous. These pundits may be in for even greater surprises in the relatively near future."

A Tuesday Politico article warned that with Roberts having inoculated himself and the court against charges of partisanship, it may have made him more able to craft and sign on to conservative opinions on dispute over same-sex marriage and voter ID laws.

William McGurn of The Wall Street Journal, responding to a suggestion that Roberts' decision had earned political capital to move rightward, said such a situation would raise — not answer — questions.

"If earning 'sufficient political capital' is simply a consequence of his ruling, Justice Roberts cannot be blamed," McGurn wrote. "If it was the aim, however, and it led to his voting as chief justice in a way he would not have voted as an associate justice, he has raised rather than resolved questions about the integrity of the Roberts court."

A new Rasmussen poll shows a jump in negative perceptions of the court after the decision, with 33 percent saying the court was doing a good or excellent job before the health care ruling as opposed to 36 percent before. The 28 percent now saying the Supreme Court is doing a poor job is an 11-point jump from the prior week. Thirty-seven percent now believe the court is too liberal and 22 percent think it's too conservative, up from 32 percent saying it was too liberal, and down from 25 percent saying too conservative.