On the Gunwalker report from the DoJ IG:

The White House’s refusal to release communications related to the Fast and Furious gun-walking program and the refusal of a White House official to be interviewed about the matter “made it impossible” for the inspector general (IG) of the Justice Department to “pursue that aspect of the case,” the IG, Michael Horowitz, testified.

He added that the sought-after White House interview and communications constituted “a lead we wanted to follow.”
 But it was a 'complete investigation that cleared the AG', etc. ad Bullshit.


Also from the IG,
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.
...
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."
You'll notice, at the end of this, that Rep. Cummings is playing "Bush started it!"  As if that would somehow excuse the guilty in this from responsibility for their actions and inactions.

From Grassley's statement on the report:
“At first glance, the Inspector General’s report reaffirms virtually everything that Congressman Issa and I have already reported.  Operation Fast and Furious was the height of irresponsibility on the part of a number of people from the ATF Phoenix field office all the way up to the Justice Department headquarters.  And, we still don’t know the full extent of any White House involvement because they refused to be transparent and provide documents requested by the Inspector General.  

“It’s clear that both the ATF and the Justice Department failed to provide meaningful oversight of Operation Fast and Furious.  They ignored warnings from employees, and frankly, failed to do their jobs.  It took the death of our own Border Patrol Agent, action by a courageous whistleblower, and intense scrutiny from Congress before they even took note of what was happening under their own eyes.  Even then, they wouldn’t come clean with how bad it really was until after they had sent a false letter and retracted it eight months later.

“It’s particularly discouraging that this all could have been stopped early on if people had just read the wiretap applications.  The Inspector General noted that anybody reading those documents should have seen the red flags. The law requires that certain senior officials authorize those applications, and the Inspector General found that they did so without reading them(That's assuming they DIDN'T read them...).  I’m glad that the OIG is joining me and Chairman Issa in urging the Justice Department to move to unseal the wiretap applications so that the American people can read them and make up their own minds.

“The President also appears to be abusing his authority to exert executive privilege.  The White House rightly allowed the Inspector General to make public a small subset of the documents withheld from Congress under his claim of Executive Privilege, but it continues to shut out Congress’ access to the rest of the documents.  It proves that this subset of documents could have been released earlier, and the President was merely thumbing his nose at Congress by claiming Executive Privilege on the eve of the contempt vote against Attorney General Holder for withholding the documents.

“It’s time to hold people accountable.  Attorney General Holder is out of excuses for action.