The Department of Justice released a statement late Tuesday night, NBC News reports, warning House Democrats not to hold AG Barr in contempt, ending any possibility of the two parties - the DOJ and the House Judiciary Committee - working out a deal for Barr to testify.
The judiciary committee initiated the proceedings when Mr Barr defied a congressional subpoena and refused to submit an unredacted version of Special Counsel Robert Mueller's report. If Democratic efforts to impeach Trump are focused on obstruction, which they nearly have to be given Mueller's verdict that Trump didn't conspire with Russian Federation, why do they need the unredacted report to proceed with "oversight"?
Executive privilege is a right claimed by presidents to withhold information about internal executive branch deliberations from other branches of government.
A Justice department official said Trump did not waive executive privilege by sharing materials with Mueller, adding that the assertion of executive privilege is not an obstacle to potential testimony by Mueller.
But Pelosi argued that such stonewalling by the Trump administration is meant to distract the public from their efforts to undermine the Democratic legislative agenda on issues ranging from health care to climate change.
House Speaker Nancy Pelosi backed the chairman's decision.
"Some of the things they've said about the attorney general, they've accused him of everything but abandoning his children to wolves", Sen.
Democrats argue that the subpoenaed records lost the shield of executive privilege when the president allowed McGahn to share the documents with his lawyer and to discuss them with Mueller. The department rejected the offer. But those talks ultimately stalled.
During Wednesday's meeting, Nadler said the Justice Department was heading in the wrong direction with its "dramatic step" in asking Trump to invoke protective assertion of executive privilege.
"The Department seemed open to sharing these materials with us earlier today. The department's legal arguments are without credibility, merit, or legal or factual basis".
Republicans accuse Democrats of attempting to discredit Barr because the attorney general is reviewing the origins of the Trump-Russia investigation and looking into allegations that the Obama administration spied on Trump's campaign.
"I ask you to recognize that craven and insincere politics yield anemic dividends for Americans who have asked us to legislate", Collins said.
The White House is thus far blocking McGahn from producing documents demanded by the Judiciary Committee.
He said what the online letter signed by hundreds of former prosecutors stands for is the idea that if any American other than the president had committed the acts detailed in the Mueller report, there would be enough evidence to indict them for obstruction of justice.
Republicans have largely united behind the President, with Senate majority leader Mitch McConnell declaring "case closed" on Mueller's Russian Federation probe and potential obstruction by Mr Trump. McConnell said Democrats are "grieving" the result.
McGahn is also being asked for documents related to "the subject of investigating James Comey or Democratic presidential candidate Hillary Clinton [and on] presidential pardons, whether possible or actual for Paul Manafort, Michael Flynn, Michael Cohen, Rick Gates, Roger Stone, individuals associated with the Trump campaign, or individuals involved in matters before the U.S. Attorney's office for the Southern District of NY".
Barr noted that in speaking to Mueller personally, the special counsel had not taken issue with the substance of his release but that he did not know the minds of unnamed members of Mueller's team.