Moments before the Senate confirmed John Roberts as the next chief justice of the United States in a 78-22 vote on Thursday, Senate Majority Leader Bill Frist, R-Tenn., said the court “will embark upon a new era in its history, the Roberts era.”

But just what that era will be like is still unknown.

As a former member of the Reagan administration, Roberts is openly right-leaning, and some expect he will follow closely in the footsteps of his predecessor, William Rehnquist.

But, as with all justices, experts say his votes on some issues may come as a surprise to observers.

As chief justice, Roberts will head a court that will likely be faced with a number of controversial issues in the coming years, such as same-sex marriage, privacy and abortion.

Roberts’ answers during the Senate hearings indicated some actions he may take as chief justice.

In particular, “he offered support for the right of privacy,” said Gary Rowe, a UCLA law professor.

With the growing attention toward privacy, Rowe said this was an answer that went a long way toward easing some of the concerns many Democratic senators had about appointing Roberts as chief justice to the Supreme Court.

On these and other issues, some expect Roberts to take a more literal reading of the U.S. Constitution.

“John Roberts has indicated that he will interpret the Constitution in a very strict manner, not allowing for those sort of more broad ... interpretations of the Constitution,” said Gabe Rose, events director for Bruin Democrats.

Rose used the example of same-sex marriage, which has recently become a critical subject of public discussion.

In Rose’s opinion, there is some constitutional protection for same-sex marriage, though it is clearly not specifically referenced in the Constitution.

But Rose said that, based on Roberts’ past statements, he does not expect the chief justice to approach his reading of the Constitution in such a way that would allow for same-sex marriage.

“It’s very likely he could rule against things like civil rights for same-sex couples,” Rose said.

In analyzing Roberts’ role on the Supreme Court and how he will vote on the important issues, many experts look to Rehnquist’s legacy for pointers.

Given that both Roberts and his predecessor are considered conservative, his appointment will not precipitate a substantial change in the politics of the court, said UCLA law Professor Daniel Lowenstein.

“Roberts is replacing someone who is quite conservative ... so it doesn’t change the direction of the court,” he said.

But Kenneth Karst, professor emeritus at the UCLA School of Law, warned against making assumptions about Roberts’ votes based on his political views and against drawing too close a comparison between the new chief justice and his predecessor.

“I don’t think he’ll just be a clone for Chief Justice Rehnquist,” Karst said.

“He may be more sympathetic than the chief justice was to some kinds of causes that are dear to liberals, but he may be more conservative.”

And Karst said making predictions about how a Supreme Court justice will rule is always a tricky task, because justices have often demonstrated unpredictable voting patterns in the past.

“Anyone who makes any pronouncements here is going way out on a limb,” he said.

The more controversial appointment will come when President Bush nominates a replacement for Justice Sandra Day O’Connor, who resigned from her seat in July.

O’Connor was often a swing vote for major decisions, so the appointment of her replacement has the potential to cause a drastic shift in the court, Lowenstein said.