House oversight committee chairman Rep. Darrell Issa and Iowa Republican Sen. Chuck Grassley are asking the Department of Justice’s internal investigator to hold accountable anyone who retaliated against or threatened to retaliate against Operation Fast and Furious whistleblowers.

In a Friday letter to the DOJ’s Inspector General Michael Horowitz, Grassley and Issa said they’re now concerned retaliation is much more likely following Thursday’s votes to hold Attorney General Eric Holder in criminal and civil contempt of Congress.

“We just learned that ATF senior management placed two of the main whistleblowers who have testified before Congress about Fast and Furious under the supervision of someone who vowed to retaliate against them,” they wrote before describing how senior political figures have made dangerous threats before.

Grassley and Issa said that in early 2011, right around the time Grassley first made public the whistleblowers’ allegations about Fast and Furious, Scot Thomasson – then the chief of the ATF’s Public Affairs Division – said, according to an eyewitness account: “We need to get whatever dirt we can on these guys [the whistleblowers] and take them down.”

Thomasson also allegedly said that: “All these whistleblowers have axes to grind. ATF needs to f—k these guys.”

According to Grassley and Issa, when Thomasson was asked about whistleblowers’ allegations that guns were allowed to walk, Thomasson said he “didn’t know and didn’t care.”

Grassley and Issa have given Horowitz until July 6 to answer whether Thomasson was “admonished” for those threats against whistleblowers, how he got his job in the first place and how the DOJ and ATF are going to make sure he doesn’t retaliate against whistleblowers moving forward.

The two lead Fast and Furious investigators also released new, never-before-public documents that show officials in ATF’s Washington headquarters were trying to cover up Fast and Furious two weeks before Grassley ever even asked about it.

Grassley didn’t confront the Justice Department or ATF with those questions until Jan. 27, 2011, but ATF headquarters had prepped internal talking points as early as Jan. 12, 2011.

In that Jan. 12, 2011, memo, ATF officials laid out expected questions about gunwalking in Fast and Furious and Border Patrol agent Brian Terry’s murder with Fast and Furious weapons – and canned answers ATF officials were supposed to give to press or anyone else asking about it.

For instance, a couple of expected questions include: “Border Patrol Agent Brian A. Terry was shot and killed after he and his team encountered several suspects near Rio Rico, Ariz. At least four suspects are in custody while one is still being pursued. Was a gun trafficked in this case used in the murder?” and “We understand that a firearm bought in connection with this ATF investigation was used to murder Border Patrol Agent Brian A. Terry. Can you please comment on this information?”

ATF officials were encouraged to not respond to those questions. Instead, they were told by leadership in Washington to give one of these answers spinning his murder to stress ATF’s need to accomplish its mission with Fast and Furious:

-“The death of Agent Terry in tragic and is a sad and dark day for all of law enforcement. We’ve lost one of our own. This is another example of the dangers faced by law enforcement every day across this country when pursuing these violent criminals.” -“Agent Terry’s death is the exact reason why we must continue going after those who are determined to destroy the lives of so many innocent individuals in our communities by plying their illicit trade. For those who would say it is Mexico’s problem, I say Agent Terry’s death and all of those who have perished because of this violence prove that this challenge belongs to everyone.” -“The investigation into the murder of Agent Terry is active and ongoing. ATF has pledged its support and resources to bring to justice the perpetrators who are guilty of that crime. I won’t say anything here today to jeopardize that investigation or the subsequent prosecution of those responsible for this terrible crime.” -“The murder of Agent Terry is a tragic loss that has been felt throughout the United States and underscores the dangers that law enforcement officers face every day. As the investigation continues into this heinous crime, our hearts go out to Agent Terry’s family and his fellow Border Patrol Agents who continue to risk their lives to protect the citizens of our great Country.”

Grassley and Issa released other internal documents, including emails, with their Friday letter to Horowitz. The documents show that soon-to-be-former Assistant Attorney General Ron Weich – who is resigning to lead the University of Baltimore School of Law – may have been in on this cover-up plan.

Weich was the author of a false Feb. 4, 2011 letter to Grassley, in which he denied – on behalf of Holder – gunwalking ever took place. Holder’s DOJ withdrew that letter 10 months later, in December 2011.

Weich and now former acting ATF director Ken Melson – who was promoted into DOJ leadership after he secretly deposed Congress without DOJ or ATF counsel – were cc-ed on emails from late January 2011.

Those emails discuss how the DOJ and ATF planned to respond to Grassley’s request for information.

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