(ABC News)

This morning on "This Week," Rep. Darrell Issa, R-Calif., continued pressing a conspiracy theory that the botched "Fast and Furious" operation could have been part of a larger plan by the Obama administration to push through tougher gun laws in the United States. But Issa had no firm evidence to back the claim, and said he could not be certain that gun control efforts were ever an original aim of sending guns across the border.

"Here's the real answer as to gun control. We have e-mail from people involved in this that are talking about using what they're finding here to support the - basically assault weapons ban or greater reporting. So chicken or egg? We don't know which came first; we probably never will," Issa said this morning on "This Week." "We do know that during this - this 'Fast and Furious' operation, there were e-mails in which they're saying we can use this as part of additional reporting or things like assault weapons ban. So the people involved saw the benefit of what - what they were gathering. Whether or not that was their original purpose, we probably will never know."

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Issa's response came after I challenged him on comments he made in April at an NRA convention to NRA News' "Cam & Company" program, where he said, "Could it be that what they really were thinking of was in fact to use this walking of guns in order to promote an assault weapons ban? Many think so. And they haven't come up with an explanation that would cause any of us not to agree."

Issa's comments in full are below.

TAPPER: You really think that there's a possibility that they were sending guns across the border not because they were trying to get people in the Mexican drug cartels, not because they were trying to figure out drug - I mean, gun trafficking, but because they were trying to push gun control?

ISSA: Two things quickly. First of all, this was so flawed that you can't believe they expected to actually get criminal prosecutions as a result of it. So the level of flaw - flaw - flaw, if that's a word, here is huge.

But here's the real answer as to gun control. We have e-mail from people involved in this that are talking about using what they're finding here to support the - basically assault weapons ban or greater reporting.

So chicken or egg? We don't know which came first; we probably never will. We do know that during this - this Fast and Furious operation, there were e-mails in which they're saying we can use this as part of additional reporting or things like assault weapons ban. So the people involved saw the benefit of what - what they were gathering. Whether or not that was their original purpose, we probably will never know.

And I - and I take people at their word that this started off in some way as an idea where they could get good information, they could, in fact, roll up bad guys. But after it was out of control and people are saying, we're letting too many guns walk, those kinds of e-mails occurred, we - we have people who also were being opportunists.

And, remember, Eric Holder issued a four-state reporting for long rifles and used what he had had here. Right in the middle of the scandal, he issues that for four states. They never needed this information. They never needed the reporting to get this information. These federally licensed gun dealers came to ATF and told them they had straw-buyers, told them they had suspicious buyers, and turned them on to the very people. And one of these people bought over 700 weapons, just one straw-buyer.

So it's very clear the system was working, where ATF was getting information voluntarily from licensed gun dealers. They don't need the additional reporting, but they got it anyway, and they used gun violence to the border and this operation as part of it. So I think when you look at the chicken or egg, there's proof that they certainly were opportunist.

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