Chip Somodevilla/Getty Images(WASHINGTON) -- The House Oversight Committee voted Wednesday to recommend the full House hold Attorney General Bill Barr and Commerce Secretary Wilbur Ross in contempt of Congress, after President Donald Trump asserted executive privilege over materials related to the committee's census investigation.

The panel adopted the contempt resolution on a mostly party line vote of 24-15 on Wednesday afternoon, with Republican Rep. Justin Amash notably joining all Democrats in voting for the resolution while all other Republicans voted against.

The privilege assertion marks the latest escalation in the battle between the Trump Administration and House Democrats investigating Ross' move to add a citizenship question to the 2020 census, which Democrats claim was intended to intimidate immigrants and minorities, and depress the party's representation across the country.

House Oversight Chairman Elijah Cummings has accused both the DOJ and Commerce Department of stonewalling his investigation by withholding documents and preventing witnesses requested by the committee from testifying on the issue.

“For months, the Trump Administration has claimed that the decision to add the citizenship question was made at the Department level rather than at the White House,” Cummings said. “But now the president is asserting executive privilege over all of these documents. This begs the question—what is being hidden?” he said in opening remarks.

Cummings said the committee has obtained evidence that shows Ross was pushing staff to add the citizenship question months before the department made the request, and that he was doing so at the urging of the White House.

“We also now have evidence that President Trump’s advisers began discussing the citizenship question long before he took office,” Cummings said. “After the inauguration, President Trump discussed the idea with his top White House aides, Reince Priebus and Steve Bannon, who in turn pressed it with Secretary Ross.”

Assistant Attorney General Stephen Boyd argued in a letter Tuesday that the department has sought to engage in good faith with Cummings and handed over thousands of documents relevant to its investigation. Boyd accused the committee of refusing to engage with the department over a "limited subset" of the requested documents that might be privileged information.

"The Committee has failed to abide by the constitutionally mandated accommodation process by declining to negotiate over the scope of the subpoenaed materials or to recognize legitimate executive branch interest, as well as by its premature decision to schedule a contempt vote," Boyd said in the letter.

Boyd also addressed criticism from the committee on the DOJ blocking testimony from John Gore, principal deputy assistant attorney general for the civil rights division. The department contends that Barr had only instructed Gore not to testify after the committee declined the department's request to have counsel accompany him in his transcribed interview.

Reacting to the privilege letter in the committee hearing Wednesday, Cummings said it was part of a broader effort by the Trump Administration to dodge oversight from the legislative branch.

"[The Justice Department] has made very clear that they will not produce the key documents that we have identified as priorities," Cummings said. "This does not appear to be an effort to engage in good faith negotiations or accommodations, instead it appears to be another example of the administration's blanket defiance of Congress' constitutionally mandated responsibilities."

The contempt vote comes just days after Barr reached a separate agreement with House Judiciary Chairman Jerry Nadler regarding his request for underlying documents related to special counsel Robert Mueller's Russia investigation.

Nadler similarly had his committee vote to hold Barr in contempt early last month for withholding those documents, which led Barr to request that Trump invoke executive privilege over the materials the committee requested.

However, Nadler announced on Monday that he was suspending any potential move to hold Barr in criminal contempt.

House Democrats did move forward on a separate resolution Tuesday allowing committee heads to go to court to seek the enforcement of subpoenas, which could speed up their plans to sue the administration for defying subpoenas related to the census, the president's tax returns and other issues.

On Wednesday, House Democrats received an update on their multiple legal battles against the Trump administration from House counsel Douglas Letter, whose presentation appeared to tamp down expectations that Democrats' lawsuits - particularly those over the president's financial records, and a potential lawsuit over a subpoena for his tax returns - would be resolved quickly.

"Without getting into the specifics of the timing, it was sobering, that some of this will take a long time," Rep. Dan Kildee, D-Michigan, a member of leadership and the House Ways and Means Committee, said after the meeting. "The less-optimistic scenario is that we’re well into next year on some of these."

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