The House Oversight Committee filed a lawsuitTuesday against Attorney General Bill Barr and Commerce Secretary Wilbur Ross for blocking its probe into the administration’s failed efforts to add a citizenship question to the 2020 census, calling their actions a “brazen obstruction of Congress.”

Rep. Carolyn Maloney, the New York Democrat who took over as Oversight chief, said she filed the lawsuit in a federal district court in Washington, D.C. because the two departments have refused to hand over key documents as part of its probe into the origins of the now-scuttled citizenship question.

“Since the Supreme Court ruled against them— and the House of Representatives held them in contempt for blocking the Committee’s investigation— Attorney General Barr and Commerce Secretary Ross have doubled down on their open defiance of the rule of law and refused to produce even a single additional document in response to our Committee’s bipartisan subpoenas,” Maloney said in a statement.

“I am filing this enforcement action today because the Trump Administration’s brazen obstruction of Congress must not stand,” she said. “President Trump and his aides are not above the law.”

Maloney said in court documents that the aim of the probe is to protect the integrity of the census as the agency prepares to conduct the crucial count by April 1, 2020 because “many of the same officials who attempted to add the illegal citizenship question are still in place today and may be involved with executing various components of the 2020 Census.”

This past June, the Supreme Court ruled that the administration could not add a citizenship question to the census, calling its rationale for including such a question “contrived” and “pre-textual.” The Census Bureau later announced it would begin printing the forms without the questions. President Donald Trump then issued an executive order ordering the agency to collect citizenship data through other federal agencies.

In July, the House voted to hold Barr and Ross in criminal contempt of Congress. It passed along party lines by a vote of 230-198.

Ross, whose department oversees the census, has claimed— in court filings, Congressional testimony and public statements— that he was adding the question at the request of the Justice Department to enforce the Voting Rights Act. However, it later emerged in court documents that he not only asked the department to make the request but had been discussing adding the question for months with other officials.

Barr has blocked key Justice Department officials from testifying before the committee, including blocking a DOJ employee from answering 150 questions about the process.

Maloney succeeds the late Rep. Elijah Cummings, D-Maryland, who died last month. She is the first woman to lead the powerful committee, one of the three overseeing the impeachment inquiry.

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