Congressional investigators will get another crack at one of the Justice Department principals for Operation Fast and Furious, a weapons sting that has set up an oversight battle between Republicans and the Obama administration.

Dennis Burke, the former U.S. attorney for Arizona, will be interviewed by the office of Oversight and Government Reform Chairman Darrell Issa (R-Calif.) for the first time since an interview over the summer was cut short.

When Senate Judiciary ranking member Chuck Grassley (R-Iowa) first asked the Justice Department about allegations that a gun-smuggling investigation on the Southwestern border allowed hundreds of assault weapons to escape into the hands of Mexican drug cartels, Burke denounced Grassley for even asking the question.

“What is so offensive about this whole project is that Grassley’s staff, acting as willing stooges for the gun lobby, have attempted to distract from the incredible success in dismantling [Southwest border] gun trafficking operations,” Burke told Justice Department lawyers who were preparing a response.

Pushing lawyers to “categorical[ly]” deny the allegations, Burke bristled when other officials raised the “risks” of an aggressive denial. “What risk?” Burke wrote to colleagues.

Grassley had questioned whether two AK-47s that had been found at the site of U.S. Border Agent Brian Terry’s murder had been tracked by the Bureau of Alcohol, Tobacco, Firearms and Explosives’ investigation.

In fact, they had been. But Burke, in a Feb. 4 email, blasted Grassley’s office for “lobbing this reckless despicable accusation that ATF is complicit in the murder of a fellow federal law enforcement officer.”

The same day the email was sent, the Justice Department would send a letter to Grassley broadly denying that ATF investigations had allowed guns to “walk,” which means ending surveillance on guns suspected to be in transit to criminal networks.

Attorney General Eric Holder has since conceded the letter contained false information, and the letter was formally withdrawn by the Justice Department on Dec. 2.

“Any instance of so-called gunwalking was unacceptable. This tactic was unfortunately used as part of Fast and Furious,” Holder told Senators at a Nov. 8 Judiciary Committee hearing. “This should never have happened.”

Burke received frequent oral and written briefings from the operation’s lead prosecutor and from ATF officials heading it. Congressional investigators have asked whether Burke knew gunwalking tactics were being used at the time he told Justice Department lawyers to deny to Congress they were, and if not, how he could have been ignorant about them.

In an Aug. 18 transcribed interview, Burke opened by saying he was taking responsibility for Fast and Furious. “I’m not going to say mistakes were made. I’m going to say we made mistakes,” Burke said, according to a source close to the investigation.

He hinted at his role urging Justice Department lawyers to deny Fast and Furious allowed guns to walk, saying, “I regret that I was strident” when Grassley first contacted the Justice Department.

Burke said he didn’t have “full knowledge” of the investigation at the time the letter was sent and talked about how his “attitude” about the case had “evolved.”

Pressed repeatedly about what exactly he had learned since he urged the Justice Department to broadly deny guns were walked, Burke cited matters such as how long the case took and that there should have been more questions about “anecdote[s]” from Fast and Furious that “occurred in Mexico.”

Unlike other officials, such as Kenneth Melson, the former head of ATF, Burke did not describe a process of learning that the investigation was allowing hundreds of assault weapons to escape to Mexican drug cartels.

Burke eventually asked to “come back to you on that” so he could “give it more thought.”

Today’s interview represents the continuation.

“These aren’t the answers you would anticipate from someone who was in the dark and had only recently come to learn about the outrages in Fast and Furious,” the source close to the investigation said.

A Dec. 7 “frequently asked questions” memo from Democrats on the House Oversight panel sent to Democratic staff and obtained by Roll Call asks whether Burke “approve[d]” of gunwalking in Fast and Furious.

“No, according to then-U.S. Attorney Dennis Burke,” the memo said, citing other portions of Burke’s Aug. 18 interview in which he denied approving the tactic’s use and said he did not “recall” knowledge of its use.

“Did you ever discuss with [ATF Special Agent-in-Charge William Newell] a deliberate tactic of non-interdiction to see where the weapons ended up? To see if they ended up with the [cartel] in Mexico?” Congressional investigators asked Burke.

“I do not recall that at all,” Burke said.

However, in January 2010, Burke was prompted by lawyers in his office to decide on two tactical approaches in Fast and Furious, according to documents released by the Justice Department on Oct. 31.

Emory Hurley, the lead prosecutor on Fast and Furious, discussed the approaches in a Jan. 5, 2010, memo about the main target of the case, Manuel Celis Acosta, who was suspected of trafficking more than 600 firearms to Mexico.

“In the past, ATF agents have investigated cases similar to this by confronting the straw purchasers and hoping for an admission that might lead to charges,” Hurley wrote. “Straw purchasers” are individuals who buy guns on behalf of gun traffickers.

Rather than use that approach, “Local ATF favors pursuing a wire[tap] and surveillance to build a case against the leader of the organization,” Hurley wrote.

Mike Morrisey, also from the Arizona U.S. attorney’s office, forwarded the memo to Burke via email and said, “local ATF is on board with our strategy but ATF headquarters may want to do a smaller straw purchaser case.”

Burke replied, “Hold out for bigger. Let me know whenever and w/ whomever I need to weigh-in.”

In an Oct. 21 memo prior to that correspondence, Hurley had written that “[a]gents have not purposefully let guns ‘walk.’”

Issa’s office has not yet interviewed Hurley.