Republican Sen. John Cornyn asked the judge about a speech in which she said, "judges may develop a novel approach to a... set of facts... that pushes the law in a new direction."
"Do you believe judges ever change the law?" Cornyn asked.
Sotomayor explained she meant that judges do not change the law but how to interpret certain laws. That interpretation can change, she said, based on changing laws from Congress, social norms, or technological developments that change the facts in a case.
"I'm passionate about the practice of law and judging," she said, "passionate in the sense of respecting the rule of law."
She intended to tell her audience in that speech, she said, "Don't participate in the cynicism that people express of our legal system."
Cornyn also asked about a 2001 speech in which she spoke about how difference between men and women can affect their professional lives.
A different life experience, Sotomayor said, "helps you listen and understand."
"It doesn't change what the law is and what the law commands," she added.
She explained how one's experience as a prosecutor may be applicable in a criminal case but not an antitrust suit.
"It improves the public confidence that there are judges with a variety of different backgrounds on the bench," she said, ensuring that "all arguments will be understood."
As on Tuesday, Republicans on the Senate Judiciary Committee are using Sotomayor's confirmation hearing to raise doubts about her fairness, while Democrats are portraying the 55-year-old New Yorker as a model jurist.
"I suspect the White House is delighted with the nominee's first day under questioning," CBS News chief legal analyst Andrew Cohen says. "She didn't make any gaffes, she kept her cool, she didn't reveal many hints about her positions in future cases and she explained patiently all those out-of-court statements that got her in a bit of trouble."
Under questioning Tuesday, Sotomayor tried to take away one line of Republican attack when she distanced herself from the man who nominated her, President Barack Obama.
Asked whether she shared Mr. Obama's view - stated when he was a senator - that in some cases, the key determinant is "what is in the judge's heart," Sotomayor said she does not.
"I wouldn't approach the issue of judging in the way the president does," she said. "Judges can't rely on what's in their heart. They don't determine the law. Congress makes the laws. The job of a judge is to apply the law."
Time and again, she put her record on display to answer charges of bias.
Sotomayor backed away from perhaps the most damaging words that had been brought up since Mr. Obama nominated her seven weeks ago - a comment she made on several occasions suggesting that a "wise Latina" judge would usually reach better conclusions than a white man. She called the remark "a rhetorical flourish that fell flat."
"It was bad because it left an impression that I believed that life experiences commanded a result in a case, but that's clearly not what I do as a judge," Sotomayor said.
Republicans were not satisfied with her answers.
Sen. Lindsey Graham, R-S.C., said he could end up voting for Sotomayor but wants to make sure she is the judge with what he called a moderately liberal record, not a liberal activist.
"That's what we're trying to figure out - who are we getting here?" he said.
Despite the Republican attacks, Cohen says, "you get the sense that even they don't really have a ton of ammunition to use against her - remember she was twice confirmed by this same Committee in the 1990s."
More coverage of the Sotomayor confirmation hearings: