Soon after President Obama nominated Judge Sonia Sotomayor to the Supreme Court, news outlets began featuring round-the-clock discussion about the role of the judiciary, judicial activism, and judges’ political views.

Of course, judges are entitled to hold political opinions, just as everyone is, but the problem of activism arises when judges allow their political views to influence their decisions.

As columnist David Brooks pointed out, the difference between a judge and a legislator is similar to the difference between a reporter and a columnist. Ideally, though it’s not always the case, a reporter ought to uphold the impartial standards of the profession. The columnist can take a more political approach, just as the legislator can. Everyone is treated fairly when both the reporter and the judge avoid injecting political views into his or her work.

During his own confirmation hearing, John Roberts, now chief justice of the Supreme Court, provided a good description of a judge’s role.

“Judges and justices are servants of the law, not the other way around. Judges are like umpires. Umpires don’t make the rules; they apply them,” Justice Roberts said.

“The role of an umpire and a judge is critical,” he continued. “They make sure everybody plays by the rules. But it is a limited role. Nobody ever went to a ballgame to see the umpire. Judges have to have the humility to recognize that they operate within a system of precedent, shaped by other judges equally striving to live up to the judicial oath.”

So, the job of a judge is to call the balls and strikes according to the rules. That is, he or she must uphold the Constitution and strictly adhere to the law when rendering a verdict.

To take Justice Robert’s analogy a bit further, think of how umpires call strikes. Major League Baseball has strict rules about the strike zone�”the area through which the pitcher must throw the ball for a strike.

If an umpire discards the established rules and relies on his interpretation of the strike zone, he risks giving an unfair advantage to the pitcher or batter. The best umpires are those who consistently follow the established rules. The same should be true of judges.

While I am proud that a Latina has been nominated to the Supreme Court and I admire Judge Sotomayor’s background and life story, they are not the basis for her judicial rulings. Those should be based on her honest and fair reading of the law.

Some have rhetorically argued that, if judging is like umpiring, with discretion or judgment involved, why don’t we have a computer calling balls and strikes? That is not a serious argument. No one has ever contended there is no human judgment involved in umpiring or judging. The point is that judges, like umpires, should exercise their judgment on the basis of established rules.

Judges’ decisions must not be a result of sympathies or personal identity, and judges must not try to bend or mold the law to accommodate their feelings. There’s a reason the famous Lady Justice statue weighing the scales wears a blindfold.

Judge Sotomayor visited my office recently to introduce herself and begin a dialogue about her record on the bench and her judicial philosophy. That dialogue will continue as my Senate colleagues and I explore her record in what I expect will be a fair and respectful confirmation process. What we learn will help me decide how to vote on her nomination.

(U.S. Sen. Jon Kyl is the Assistant Republican Leader and serves on the Senate Finance and Judiciary committees. Visit his Web site at www.kyl.senate.gov.)