WASHINGTON -- Firefighter Frank Ricci, scheduled to testify about Sonia Sotomayor's ruling against his reverse discrimination lawsuit, was targeted for criticism Monday by powerful liberal groups who support her confirmation to the Supreme Court.

Senate Judiciary Committee Republicans decided last week to make Ricci, a white New Haven, Conn., firefighter, one of their showcase witnesses on Thursday. His reverse discrimination suit against the city of New Haven was rejected by a three-judge appeals court panel that included Sotomayor.

Ricci challenged New Haven's decision to scrap the results of a promotion test because too few minorities scored high enough to qualify. Two weeks ago the Supreme Court, on a 5-4 vote, overturned the decision to dismiss the suit.

People for the American Way, a liberal group, said Monday that Ricci got his firefighting job in New Haven "by claiming discrimination under the Americans With Disabilities Act, which protects Americans from discrimination over disabilities." Ricci has dyslexia, a learning disability that impairs the ability to read.

"I don't think Mr. Ricci thought that his being hired was a case of reverse discrimination against those who weren't disabled," said Marge Baker, the group's vice president. "But you can't have it both ways; these laws can't be good when you use them to protect yourself and bad when they're used to protect someone else."

Calls to Ricci's firehouse in New Haven met with busy signals.

Conservatives called the liberal group's complaints "a smear campaign."

"It is beneath both contempt and the dignity that this process demands," said Sen. Orrin Hatch, R-Utah, during his opening statement.

"They are sickening and represent the worst of gutter politics," said Karen Torre, Ricci's lawyer.

Republicans referenced Ricci's case several times Monday and characterized it as an example of what they called Sotomayor's tendency to favor one race over another.

"It seems to me that in Ricci, Judge Sotomayor's empathy for one group of firefighters turned out to be prejudice against another," said Sen. Jeff Sessions of Alabama, the top Republican on the Senate Judiciary Committee.

One conservative group, the Judicial Confirmation Network, is trying to rally conservatives behind Ricci.

"Sotomayor's liberal interest group supporters have launched an attack campaign to intimidate and smear him," the group said in an e-mail to its supporters. "They have chosen the wrong target. People who run into burning buildings to save others do not frighten easily."