This is a rush transcript from "Hannity," October 7, 2011. This copy may not be in its final form and may be updated.

SEAN HANNITY, HOST: We probably would not know much about the Operation "Fast and Furious" controversy if it were not for the tireless pursuit of the facts by Congressman Darrell Issa, who is the chairman of the House Oversight and Government Reform Committee. He joins us now with the very latest on this investigation.

Congressman, welcome back, sir. Thank you for being with us.

REP. DARRELL ISSA, R-CALIF., HOUSE OVERSIGHT COMMITTEE CHAIR: Thanks for having me on, Sean, and thanks for covering this important issue, in which Americans and Mexicans lost faith in their government because of what was done by our officials in the Justice Department.

HANNITY: Well, there's a couple of things that bother me about this. And I think it comes down to a very simple question: what did the attorney general know, when did he know it, and did he tell you the truth when he testified on May 3 of 2011 and said, I probably just heard about this for the first time in the last few weeks? We know that is a lie, correct?

ISSA: We certainly know that he failed to meet the duty of candor. If he now says, well, I thought you were asking a different question, he certainly stretched what one could answer when you said, when did you know about. So either when or about seemed to have tripped him up.

HANNITY: Failure to meet the duty of candor. Good thing you are in the political business, because in my little old world I call that a lie.

ISSA: You know, in any reasonable voter's mind, in any reasonable citizen's mind, he owed us an answer, and he didn't give it to us truthfully. There's no question about that.

There is some technical terms for what he did or didn't do. And one of the reasons that we want him back before the committee to answer fully and honestly and completely on this one subject is, he owes us that. You don't come before the Judiciary Committee headed by Lamar Smith and not answer questions truthfully when it's the committee you report to, it's the accountability to the American people.

And very clearly he knew about "Fast and Furious." How much he knew, we would like to be able to ask him.

HANNITY: What about these new documents that have surfaced that show that the attorney general was sent briefings on "Fast and Furious" as far back as July of 2010, which again contradicts his statement to Congress? We have got these two Justice Department officials in this e-mail exchange October 18 of 2010. It's a tricky case given the number of guns that have walked, but a significant set of prosecutions. The reply, I'm not sure how much grief we get for gun walking. It may be more like, well, finally they are going after people who send guns down there.

So it seems like they were calculating the political fallout fairly early on.

ISSA: They absolutely were. And that's one of the points, Sean, is the reckless disregard for the effects that 2000-plus assault weapons, including 37 50-caliber sniper rifles that have brought down aircraft in Mexico -- that's the real crime here. Yes, we can eventually figure out what Lanny Breuer knew and how much he orchestrated it and how bad his judgment was, and certainly Eric Holder has got a lot to account for, but the American people and the people in Mexico that relied on us to cooperate to help them, they are owed a change that is permanent. If you will, we hope for a change you can believe in.

HANNITY: You said that we have a paper trail of so many people knowing that the only way the attorney general didn't know is he made sure he didn't want to know.

ISSA: Absolutely.

HANNITY: Well --

ISSA: Look, Lanny Breuer was running this operation to a great extent. He had intimate knowledge. He thought it was a good operation with, in fact, bad execution. When you have the No. 2, the No. 3, and now his chief of staff all very involved in this, they are in that paper trail, it's hard to believe that he wouldn't know.

And, Sean, if I can just add one date, March of 2009. The attorney general flies to Mexico City and makes a significant speech in Mexico.

HANNITY: That's right.

ISSA: Telling about what they are going to do. You can't have that level of promise and commitment, and then say that for the next two years you didn't know about it.

HANNITY: You know, I'm a big baseball fan. Didn't Roger Clemens go under oath before a congressional committee?

ISSA: Roger Clemens failed to meet a duty of candor in the eyes of the Justice Department. And he was tried, and, quite frankly, was basically bankrupted by our government prosecuting him.

Now, we can debate about whether he deserved it, but Henry Waxman referred that and in fact led him to trial. Eric Holder certainly has some explaining to do about whether or not he was truthful to our committee.

Guys doping themselves in baseball is serious because it distorts the game. Two thousands weapons going to Mexico--

HANNITY: People die.

ISSA: -- fueled the fire. And 44,000 Mexicans are dead, and many of them by these guns.

HANNITY: All right, thank you, Congressman.

ISSA: Thank you.

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