It's been a key subject of dispute throughout the "Fast and Furious" saga but one shrouded in mystery: whether wiretap applications reviewed and approved by senior Justice Department officials should have tipped them off about the dangerous tactics being used in the operation.
House Oversight and Government Reform Chairman Darrell Issa (R-Calif.), who obtained the wiretap applications surreptitiously from a whistleblower, said yes.
Attorney General Eric Holder and Congressional Democrats who reviewed them adamantly said no.
But because the documents were under court seal, the public was only afforded a glimpse of what was in them when Issa inserted a letter that characterized and quoted from them in the Congressional Record.
Now Michael Horowitz, the Justice Department's inspector general, is broadly siding with Issa, saying in testimony before the Oversight panel today that the wiretap applications should have raised red flags to senior officials who approved them.
Asked by several Republican lawmakers at the hearing whether reading the wiretap applications would have indicated that guns were being "walked," the tactic employed in Fast and Furious, Horowitz said "yes."
He then added a more nuanced version included in the report, that someone "who was focused on the question of investigative tactics, particularly one who was already sensitive to the issue of 'gun walking,'" would have "questions about ATF's conduct of the investigations."
Officials testified to Horowitz that they reviewed the applications more narrowly for whether they met legal standards of probable cause to request the wiretaps.
And Jason Weinstein, a deputy assistant attorney general who resigned in the wake of the IG's report, said he read only the cover letter of the application, not a more detailed affidavit included that would have raised even more questions than the cover letter.
At the hearing today, Horowitz said even the cover letter should have prompted Weinstein to ask more questions or read the affidavit. And the report notes Weinstein had been briefed on the scale of Fast and Furious and knew an earlier operation from the same office - the "Wide Receiver" operation under the George W. Bush administration - had allowed guns to "walk."
"They should have an appreciation of broader issues" than just reasonable cause, Horowitz said, adding that Weinstein had an "obligation" to find out more, given his responsibility.
He noted that he previously served at the Justice Department in a position where he reviewed wiretap applications, giving him experience on how such documents are reviewed and approved.
In his resignation letter to Holder, Weinstein disagreed, portraying himself as a scapegoat of a politically motivated witch hunt.
"I recognize that, in the dynamic of internal investigations of this nature, particularly when they become enmeshed in politicized Congressional hearings, it is virtually inevitable that someone must be singled out for blame, whether the facts support it or not," he said in the letter.
Meanwhile, Issa seized on Horowitz's findings as vindication in the previously murky battle over the importance of the wiretap applications, with his office asking in a press release whether Holder and other Democrats who downplayed their significance were "willfully misleading to the American people or just plain wrong?"
Rep. Elijah Cummings (D-Md.), the ranking member on the Oversight panel who vigorously argued the wiretap applications should not have raised red flags, noted in his questioning of Horowitz that wiretap applications for Wide Receiver similarly contained warning signs and were approved anyway.