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"I think that is probably a good idea," said Sen. Arlen Specter, R-Pa. Added Rep. Dan Burton, R-Ind., "That's something that we could look into."

And on Monday, Capitol Hill sources confirmed that former Democratic Party Finance Chairwoman Beth Dozoretz intends to exercise her Fifth Amendment rights in connection with Burton's House Government Reform Committee probe into the controversial Clinton pardon of Marc Rich.

Burton has a hearing scheduled for Thursday, and Dozoretz is on the witness list. It is unclear whether she will show up at the hearing to exercise her constitutional right to remain silent, or whether she will stay away altogether.

Burton and Specter, who heads the Senate Judiciary Committee's investigation into the pardons, said they have not had formal conversations about the idea of combining investigations.

"I would be happy to talk to [Specter]," Burton said on Fox News Sunday.

The investigations began with officials searching to see if fugitive millionaire Marc Rich or his family promised donations in return for his pardon.

Federal prosecutors in New York now are investigating whether the former president commuted the sentences of four convicted swindlers in exchange for Hasidic Jewish votes for his wife during her run for the Senate, a source has said.

Also under scrutiny are a pardon and a commutation for which Mrs. Clinton's brother Hugh Rodham received nearly $400,000; two pardons on which her campaign treasurer performed legal work; and the possible role of the former president's half brother, Roger Clinton, in some other cases. 

Three Clinton Advisers Scheduled for Thursday

Three of Clinton's closest White House advisers are scheduled to appear Thursday: former chief of staff John Podesta, former White House counsel Beth Nolan and former White House adviser Bruce Lindsey.

Also expected to testify is Skip Rutherford, the president of the William Jefferson Clinton Presidential Library Foundation.

The committee wants access to the foundation's donor list to check to see if any money came in that could have been promised in exchange for pardons.

Specter said on CBS' Face the Nation that the Senate Judiciary Committee will do its best not to duplicate what the House committee's work, so "coordinated efforts, if not a joint hearing, I think would be advisable."

Democrats Welcome Idea, Attack Burton Investigation

"A lot of people do not have confidence, necessarily, in the current structure," said Sen. John Kerry, D-Mass., on NBC's Meet The Press. It's been "one hunt after another."

"The process that is set up now is not fair. Let us have a fair investigation," Rep. Chaka Fattah, D-Pa., said on NBC.

Fattah said a joint committee should have equal House-Senate and GOP-Democratic membership. "Then the president should and I think would participate," he said.

Republicans defended their work but did not dismiss the idea of a joint investigation.

"I wouldn't rule it out but our committee is conducting a fair hearing," said Rep. Christopher Shays, R-Conn., a member of Burton's committee.

Sen. Pete Domenici, R-N.M. said he would support "whatever structure is necessary so that Congress people in charge can say we have gotten all of the facts."

"Maybe there can be a bipartisan group," he added.