Washington » Utah Sen. Orrin Hatch went from a likely supporter to a staunch opponent of Supreme Court nominee Sonia Sotomayor during her three days of testimony before the Senate Judiciary Committee.

He found her answers inaccurate and incomplete. He left thinking she tried to placate senators instead of giving them insight into her decision-making. And, as a result, for the first time in his 32-year Senate career, Hatch will vote against a nominee to the high court.

The Utah Republican announced his decision Friday, but articulated the reasons in a series of interviews Monday.

"There were too many things I thought were wrong about her testimony," Hatch said on MSNBC. "Frankly, there were some answers she gave that I felt didn't make sense."

The Judiciary Committee is expected to vote on Sotomayor's confirmation today, clearing the way for a full Senate vote in the next two weeks. Most political observers, including Hatch, expect the nominee to win confirmation.

Democrats have lavished praise on Sotomayor, a 2nd U.S. Circuit Court of Appeals judge, and at least four Republicans already have announced they will back her on the Senate floor. Sotomayor would be the first Latino justice on the top court, replacing retiring Justice David Souter.

One factor in Hatch's decision could be the backlash from Utah conservatives if he voted for her, according to University of Virginia political scientist Larry Sabato.

"There is a slice of the party that has become very critical of Hatch," he said, "and no doubt they would have used a vote for Sotomayor to hammer Hatch."

But Hatch disputes politics played any role.

"I made my decision here on the merits," he said.

Hatch called Sotomayor's credentials and experience "very impressive" and her temperament "cordial and friendly," but he questioned whether she has what it takes to assume such a high post.

"Some of her cases give short shrift to constitutional rights," he said in an interview with The Salt Lake Tribune . "She's used incorrect legal standards, and she has misapplied precedent."

In particular, Hatch pointed to two cases he questioned Sotomayor about during her confirmation hearings -- one dealing with gun rights, the other with discrimination.

At issue in the gun case was whether the Second Amendment applied to states or just the federal government. In a recent ruling focused on New York's ban on nunchucks, Sotomayor said the state had the ability to restrict access to weapons. Hatch thought her reasoning relied on the wrong legal precedent, especially in light of the Supreme Court's recent ruling that the Second Amendment guarantees an individual right to gun ownership.

The National Rifle Association also has come out in opposition to Sotomayor.

The Supreme Court is likely to take up this gun-rights issue soon.

The other case involved a reverse-discrimination claim by white firefighters in New Haven, Conn., who were upset when the city tossed out a promotion exam because minorities performed poorly. Sotomayor sided with the city, which feared claims of racial bias, but the Supreme Court overturned her ruling in a 5-4 vote.

She defended her decision, saying she relied on existing precedent, but Hatch felt she showed poor legal logic.

He also questions her "commitment toward impartiality," citing past speeches in which she implied that race, gender and life experiences would affect legal rulings.

During the hearings, Sotomayor argued that the comments were taken out of context and pointed to her 17 years on the federal bench as proof that she follows the letter of the law when deciding cases.

Hatch didn't buy it.

"She offered a very different picture," he said, "at odds with the rest of her record."

He was particularly frustrated with her answers to questions about the Puerto Rico Legal Defense Fund, a liberal civil-rights group she worked with for 12 years. She said she was unaware that the fund filed briefs in a number of Supreme Court cases. Hatch felt that was implausible.

Despite his opposition, Hatch repeatedly said that he liked her personally and was impressed with her life story. She grew up in a housing project in the Bronx, reared by her mother after her father died when she was 9 years old. Now she is poised to join the highest court in the land.

"It was very difficult for me to come to the conclusion that I should vote against her," said Hatch, who normally shows deference to a president's Supreme Court picks.

Most of the Republicans on the Judiciary Committee will vote against her nomination, including Sen. Jeff Sessions, R-Ala., the ranking member.

So far the only Republican on the panel that has voiced support for her nomination is Sen. Lindsey Graham, R-S.C., who was one of her most persistent questioners during the hearings. He said she is qualified and while he doesn't agree with all of her past decisions, he found no major reason to oppose her nomination.

All of the Democrats are expected to vote for her, while Utah Sen. Bob Bennett, who is not on the committee, has announced he will also vote against her confirmation.

Bennett and Hatch were two of seven Republicans who voted for Sotomayor in 1998, when President Bill Clinton nominated her to the 2nd Circuit. Hatch said he is holding her to a stricter standard now because the Supreme Court "has the ultimate say on what constitutional law is."

mcanham@sltrib.com