WASHINGTON (Reuters) - Congressional Republicans grilled Attorney General Eric Holder Thursday over a botched gun-smuggling sting in Mexico, with one lawmaker comparing Holder to Nixon-era Attorney General John Mitchell and another saying "heads should roll."

"I have no intention of resigning," said Holder, who has headed the Justice Department since early 2009.

"I'm the attorney general who put an end to these misguided tactics," he said, defending his handling of an episode that has become an embarrassment for the Obama administration.

The 2009-2010 sting, dubbed "Fast and Furious," involved selling weapons to "straw buyers" and then tracking them as they made their way south of the border to violent Mexican drug cartels, with the goal of finding top cartel leaders.

But federal agents rarely pursued the weapons as planned. An estimated 2,000 guns went missing. Several hundred have been recovered, while many have been found at crime scenes on both sides of the U.S.-Mexico border.

Obama has shown no signs of moving to sack Holder or his subordinates. Republicans eager to score political points against the White House have been investigating for months.

"Some heads should roll," Republican Representative Jim Sensenbrenner said at an occasionally combative hearing before the House of Representatives Judiciary Committee.

Republican Representative Darrell Issa said "Fast and Furious" was "failed and flawed from the beginning."

He pressed Holder on why Justice Department documents given to investigators about Fast and Furious have included no e-mails from Holder.

"Don't you think it's a little conspicuous?" he asked.

Holder said the department's response to investigators' inquiries has been "unprecedented" and "responsive."

He said, "We have not withheld any documents that are responsive. We have withheld information about ongoing investigations."


Near the end of the more-than-five-hour hearing, Issa pressed again on the documents, saying Holder would be in contempt of Congress unless he gave a constitutional reason for holding them back.

When Holder demurred again, Issa said, "That's how John Mitchell responded."

Holder replied: "The reference to John Mitchell, let's think about that ... . Have you no shame?"

Issa shot back: "Have you no shame?"

John Mitchell was attorney general under President Richard Nixon. He was found guilty of charges related to the Watergate break-in and spent 19 months in prison.

The failures of "Fast and Furious" have already led to the resignations of two officials: the U.S. attorney in Arizona, and the acting head of the Bureau of Alcohol, Tobacco, Firearms and Explosives.

"What are you going to do to clean up this mess?" Sensenbrenner asked. "The answers that we've been getting so far are that 'Well, somebody else did it.'"

Sensenbrenner said Lanny Breuer, head of the department's criminal division and a key lieutenant to Holder, should resign. He also raised the possibility of impeachment, without specifying who should be impeached.

Senator Charles Grassley, a senior Republican, Wednesday called for the ouster of Breuer.

Holder said at the hearing the errors of Fast and Furious were "wholly unacceptable" and "must never happen again."


Holder was also asked about Supreme Court Justice Elena Kagan's role in the 2009 health care reform debate.

Smith pressed Holder for access to documents related to Kagan's role as Obama's solicitor general in health care reform. Kagan has since become a Supreme Court justice. The high court is due to hear arguments on the constitutionality of the requirement that people buy health insurance.

Some Democrats have called for Justice Clarence Thomas to be recused because of his wife's work for the right-leaning Heritage Foundation think tank, while Republicans have called for Kagan's recusal because of her work for Obama.

Smith, who is pressing for more data about Kagan's role in the discussions, asked Holder for data on who attended meetings on legal challenges on health care reform.

"I can't imagine a good reason for you to withhold them unless you assert a legal privilege," Smith told Holder.

(Editing by Kevin Drawbaugh and Xavier Briand)

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