credit: Pete Souza/The White House/Getty Images

Barack Obama probably never thought that John Roberts would be the person who saved his health care law.

The chief justice of the Supreme Court, appointed by George W. Bush, didn't exactly get off on the right foot with Obama on Day One of his presidency. As he swore in the president-elect in 2009, Roberts bungled the oath of office by misplacing the word "faithfully" - as in, "that I will execute the office of president of the United States faithfully."

It was Roberts's personality as a stickler for detail that got him caught up. As Steven Pinker noted, Roberts adhered to a strict grammatical stylebook of his own and simply moved the word "faithfully" away from the verb "execute," where it didn't belong, despite the well-known constitutional script.

Today, Roberts's attention to detail returned, in a much more substantive way - and in a fashion Obama is sure to admire. Siding with the liberal justices, Roberts ruled that Obama's so-called mandate to buy health insurance is constitutional under Congress' power to tax people who don't buy it. Roberts was the only justice to rule in favor of the law not because he thought the mandate was constitutional as it stood, but because it's a tax rather than a command - a rather nuanced analysis of the government's power.

Roberts wrote in the ruling that Congress has the power, under something called §5000A, to impose a tax on not having health insurance. "That is sufficient to sustain it," he wrote. "The 'question of the constitutionality of action taken by Congress does not depend on recitals of the power which it undertakes to exercise.' "

And, he also wrote, "It is not our job to protect the people from the consequences of their political choices."

Obama might want to send Roberts a fruit basket, or maybe he'll feel that his tie-breaking vote makes up for his role in the Citizens United decision that has allowed a swarm of super PACs to raise and spend unlimited amounts of money on ads against Obama. In a State of the Union speech, Obama shellacked Roberts' decision, and the chief justice later called Obama's actions "troubling."

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Years before that, Obama let Roberts know that he didn't even think he was qualified to be on the Supreme Court. In 2005, as a senator, Obama voted against Roberts's confirmation, saying: "I want to take Judge Roberts at his word that he doesn't like bullies and he sees the law and the Court as a means of evening the playing field between the strong and the weak. But given the gravity of the position to which he will undoubtedly ascend and the gravity of the decisions in which he will undoubtedly participate during his tenure on the Court, I ultimately have to give more weight to his deeds and the overarching political philosophy that he appears to have shared with those in power than to the assuring words that he provided me in our meeting."

Declaring his opposition, Obama said he hoped he was wrong about Roberts. "I hope that he will recognize who the weak are and who the strong are in our society," he said. "I hope that his jurisprudence is one that stands up to the bullies of all ideological stripes."

Today Obama probably agrees that Roberts executed his job faithfully.

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