Confirmation hearings began Monday for Judge John Roberts, President Bush's choice to replace the late Supreme Court Chief Justice William Rehnquist. The hearings before the Senate Judiciary Committee will cover a wide range of controversial legal and political issues.
What senators want to ask Judge Roberts depends on which side of the committee table they sit.
Opposition Democrats, like Senator Ted Kennedy of Massachusetts, make it clear they will press Judge Roberts on legal issues that involve protections for privacy and civil rights.
"So the central issue before us in these hearings is whether the Supreme Court will preserve the gains of the past and protect the rights that are indispensable to a modern, more competitive, more equal America," said Mr. Kennedy.
Most Republicans are already strongly supportive of the Roberts nomination and believe him to be a strong conservative in the mold of the man he would replace, the late Chief Justice, William Rehnquist.
Senator Charles Grassley, a Republican from Iowa, says his main concern is appointing Supreme Court justices who simply interpret the law rather than what he calls judicial activists.
"We want Supreme Court justices to exercise judicial restraint so that cases will be decided solely on the law and the principles set forth in the Constitution and not upon an individual justice's personal philosophical views or preferences," said Mr. Grassley.
Republicans and Democrats also have a general disagreement over what kinds of questions will be appropriate for Judge Roberts during the hearings.
Republicans believe questions on specific legal cases or on some legal issues in general should be out of bounds. Some Democrats are expected to press Judge Roberts for his views on a wide range of issues, including the divisive subject of abortion.
In his opening statement before the committee, Judge Roberts spoke about his approach to interpreting the law.
"I have no agenda but I do have a commitment," said Mr. Roberts. "If I am confirmed, I will confront every case with an open mind. I will fully and fairly analyze the legal arguments that are presented. I will be open to the considered views of my colleagues on the bench and I will decide every case based on the record according to the rule of law, without fear or favor to the best of my ability."
Judge Roberts once served as a law clerk to the late William Rehnquist and a number of legal experts see a similarity in their background and view of the law.
A.E. Dick Howard is a constitutional law expert at the University of Virginia.
"I think replacing Chief Justice Rehnquist with John Roberts will not, in itself, make much difference in the vote pattern of the court, because we can fairly predict Roberts' votes on cases will be, in general, like those of Rehnquist," said Mr. Howard.
Professor Howard says the more contentious confirmation battle could come later when President Bush nominates a replacement for retiring Justice Sandra Day O'Connor, perhaps the leading centrist on the high court and often the swing vote on numerous five-four rulings handed down by the nine member court.