With a Senate committee vote set for Wednesday on the nomination of Thomas E. Perez for Labor secretary, House Republicans convened a joint hearing Tuesday to examine a whistle-blower case that GOP lawmakers have been using as ammunition against him.

The witnesses at the House hearing included Sens. Charles E. Grassley of Iowa and Johnny Isakson of Georgia, two Republicans who have been highly critical of Perez, currently the assistant attorney general in charge of the Justice Department’s Civil Rights Division.

Republicans argue that Perez improperly brokered a deal with the city of St. Paul, Minn., in which the city withdrew from a Supreme Court lending discrimination case in exchange for the federal government agreeing not to join a pair of housing-related False Claims Act lawsuits against the city that were instigated by whistle-blower Frederick Newell.

Grassley and Isakson testified that the lawsuits had the potential of returning up to $200 million in damages to the Treasury, and they accused Perez of attempting to cover up his involvement and submitting misleading statements to investigators.

The case before the Supreme Court challenged the use of statistics to prove racial discrimination, and Justice Department officials reportedly were concerned that the court could strike down the practice. Grassley said DOJ sent his staff a 33-page slide show Monday night documenting career lawyers’ support for Perez’s decision in the case.

“Getting such a critical document so late in this investigation could be construed as a cover-up,” Grassley said. “I expect any remaining documents will be immediately forthcoming.”

Newell also testified at Tuesday’s hearing, held by an Oversight and Government Reform subcommittee and a Judiciary subcommittee, which featured heavy partisan bickering.

“Mr. Perez manipulated the law and pushed the limits of justice,” said Rep. Trent Franks, R-Ariz. “Mr. Perez went out of his way to find leverage to use against the city of St. Paul. He tried to cover up his deal.”

Rep. Jerrold Nadler, D-N.Y., countered: “This hearing is part of a shameful smear campaign against Mr. Perez.”

Senate Committee Vote Looms

Republicans had originally invited Newell to testify at an April 25 hearing before the Senate Health, Education, Labor and Pensions Committee, which was slated to take place directly after a committee vote on Perez’s nomination. But Chairman Tom Harkin, D-Iowa, postponed the nomination vote until Wednesday to appease GOP demands for additional information on Perez and also canceled the whistle-blower hearing.

“It’s really a shame we didn’t have the hearing two weeks ago when we called Mr. Newell in, because then we would have had all the facts on the table,” Isakson said Tuesday after the House hearing.

“We heard everything at the confirmation hearing on Mr. Perez’s side of the story,” Isakson added. “Democrats did a good job of explaining why this was not an issue. But then when we tried to get the other side of the story and they canceled the meeting, it obviously raises questions that need to be answered.”

Isakson said the delay of the confirmation vote did allow Perez to respond to several questions Republicans wanted answered. They also received requested copies of work-related emails that Perez sent from his personal email account while conducting government business and transcripts of interviews that DOJ’s Office of the Inspector General conducted during its investigation of the Civil Rights Division that Perez oversees.

“Mr. Perez responded to the questions we submitted,” Isakson said. “I’m still going through those responses to try and see if they satisfy both the spirit and intent of the questions. I’ll make my decision before the hearing tomorrow based on that.”

Past Republican Support

Despite the sniping that has surrounded Perez since President Barack Obama nominated him on March 18, no Republicans signaled that they plan to vote against him during the HELP Committee’s April 18 confirmation hearing.

While not a member of that committee, Sen. David Vitter, R-La., has promised to try to block Perez on the Senate floor because of concerns that the Civil Rights Division practiced “selective enforcement” of a voter registration law. Vitter said last month that he will demand a 60-vote threshold for confirmation.

But some other Senate Republicans might be uneasy about opposing Perez after handily losing the Latino vote in last year’s presidential election. The Harvard-educated Perez, whose family immigrated to the United States from the Dominican Republic, would be the only Hispanic in Obama’s second-term Cabinet if he is confirmed to succeed Hilda L. Solis, who resigned in January.

Back in October 2009, nine current Republican senators voted for Perez when he was confirmed as the head of the Civil Rights Division. Perez was confirmed by a vote of 72-22.

The Congressional Hispanic Caucus held a news conference Tuesday afternoon to urge Senate confirmation of Perez.

“My colleagues across the aisle are trying to smear his record at the Department of Justice,” said Rep. Linda T. Sánchez, D-Calif. “I want to be crystal clear here: Tom Perez is one of the finest advocates for civil rights that we have in this country.”

Rep. Tony Cardenas, D-Calif., noted that Republicans “have been saying rhetorically that they would like to get the Hispanic community’s attention.”

“As far as I’m concerned, if they want to earn that attention, so be it,” Cardenas said. “But what they are doing today is a shame and it’s a sham. They’re just playing political games and they’re not putting the American worker first.”

Corrected the number of current Senators who voted for Perez’s confirmation in 2009.