Jeffrey Toobin '82 delivers the Robert C. Cobb, Sr. Memorial Lecture, entitled "The Obama White House vs. the Supreme Court" at Sanders Theatre on Thursday. He lectured about the role of the Supreme Court during the recent past, dazzling the crowd with his extensive knowledge and biting humor.

Chief Justice John G. Roberts ’76 cast a strategic vote in June’s Obamacare decision, Jeffrey R. Toobin ’82 said Thursday, in an effort to shield the Supreme Court from the partisanship that rules Washington politics.

“Chief Justice Roberts did not want the Court to be seen as just another place where party battles were held,” he said as part of the Robert C. Cobb, Sr. Memorial Lecture held in Sanders Theatre.

Toobin, a staff writer for The New Yorker and the senior legal analyst for CNN, is widely regarded as one of the country’s foremost Supreme Court experts.

The Court’s four liberal and five conservative Justices, he said, are key to understanding how it works.

“If you remember one thing from my talk, that’s it. This court is driven by precisely the same party divisions that Congress is,” Toobin, a former editorial chair of The Crimson, said.

At various points in history, different ratios of liberal to conservative Justices governed the Court’s rulings, he said.

Toobin’s latest book, “The Oath: The Obama White House and the Supreme Court,” centers on the Patient Protection and Affordable Care Act case. Roberts, a conservative appointed by President George W. Bush in 2005, was one of five votes that ruled the health-care law constitutional.

Describing the ruling in June as “the great drama of last spring,” he noted that the reason for Roberts’ vote was the question that “everyone wants to answer.”

According to Toobin, Roberts “views himself as the custodian” of public opinion on the Supreme Court.

Yet, this instance of crossing the party line does not rebrand Roberts as a liberal, Toobin said.

“I assure you that as we go forward in this term and more terms to come, John Roberts will be the conservative that President Bush wanted him to be,” he said. “It just so happens that in the Obamacare case Roberts voted with the Democrats. Don’t count on that happening very often.”

Following his lecture, Toobin answered questions from the audience on topics such as the two same-sex marriage cases that could go before the Supreme Court before the end of the year, and the relationship between the President and the Court.

Francesca Coltrera, an Arlington resident, heard about the event from a friend who works in the music department. Toobin was “irreverent but he knows his stuff,” she said.

Elizabeth W. Vorenberg, the former co-master of Dunster House, called Toobin’s speech “very clear and easy to follow.”

In an interview, Toobin said Roberts’ vote would not have a large effect on the coming election.

“The Court’s decision in Obamacare removed the Court as a major issue. Obama cannot complain about the Court that saved his bacon,” he said. “The Supreme Court may not be a top of the line issue for many voters, but when you look at a president’s legacy, few issues loom larger than Supreme Court appointees.”