The 300 -page report from Democrats on the House Intelligence Committee makes the case that Trump misused the power of his office and, in the course of their investigation, obstructed Congress by stonewalling the proceedings. Based on two months of investigation, the report contains evidence and testimony from current and former U.S. officials.

“The President placed his personal political interests above the national interests of the United States, sought to undermine the integrity of the U.S. presidential election process, and endangered U.S. national security,” the report said.

The panel will vote later Tuesday, in what is expected to be a party-line tally, to send the document to the Judiciary Committee ahead of a landmark impeachment hearing Wednesday.

Ahead of the release, Republicans defended the president in a rebuttal claiming Trump never intended to pressure Ukraine when he asked for a “favor” — investigations of Democrats and Joe Biden. They say the military aid the White House was withholding was not being used as leverage, as Democrats claim, and besides the $400 million was ultimately released, although only after a congressional outcry.

Trump at the opening of a NATO leaders’ meeting in London on Tuesday criticized the impeachment push as “unpatriotic” and “a bad thing for our country.”

The findings being released Tuesday will lay the foundation for the House Judiciary Committee to assess potential articles of impeachment starting Wednesday, presenting a history-making test of political judgment with a case that is dividing Congress and the country.

Trump said he will not watch the judiciary panel’s hearing, saying it’s “all nonsense, they’re just wasting their time.”

Democrats once hoped to sway Republicans to consider Trump’s removal, but they are now facing the prospect of an ever-hardening partisan split over the swift-moving proceedings on impeaching the president.

The Intelligence Committee’s is expected to vote on the report later Tuesday in a closed-door session.

The findings are expected to forcefully make the Democrats’ case that Trump engaged in what Chairman Adam Schiff, D-Calif., calls impeachable “wrongdoing and misconduct” in pressuring Ukraine to investigate Biden and Democrats while withholding military aid to the ally.

For Republicans offering an early rebuttal ahead of the report’s public release, the proceedings are simply a “hoax,” with Trump insisting he did nothing wrong and his GOP allies in line behind him. Trump tweeted his daily complaints about it all and then added a suggestive, if impractical, question: “Can we go to Supreme Court to stop?”

Trump criticized the House for pushing forward with the proceedings while he was overseas, a breach of political decorum that traditionally leaves partisan differences at the water’s edge.

He predicted Republicans would actually benefit from the impeachment effort against him.

For the Democrats, House Speaker Nancy Pelosi faces a critical moment of her leadership as she steers the process ahead after resisting the impeachment inquiry through the summer, warning at the time that it was too divisive for the country and required bipartisan support.

Speaking to reporters at an international climate conference in Madrid, Pelosi declined to engage with impeachment questions. “When we travel abroad, we don’t talk about the president in a negative way,” she said. “We save that for home.”

Possible grounds for impeachment are focused on whether Trump abused his office as he pressed Ukrainian President Volodymyr Zelenskiy in a July 25 phone call to open investigations into Trump’s political rivals. At the time, Trump was withholding $400 million in military aid, jeopardizing key support as Ukraine faces an aggressive Russia at its border.

The report also is expected to include evidence the Democrats say suggests obstruction of Congress, based on Trump’s instructions for his administration to defy subpoenas for documents and testimony.

The next step comes when the Judiciary Committee gavels open its own hearing with legal experts to assess the findings and consider potential articles of impeachment ahead of a possible vote by the full House by Christmas. That would presumably send it to the Senate for a trial in January.

The Democratic majority on the Intelligence Committee says its report, compiled after weeks of testimony from current and former diplomats and administration officials, will speak for itself in laying out the president’s actions toward Ukraine.

Republicans preempted the report’s public release with their own 123-page rebuttal.

In it, they claim there’s no evidence Trump pressured Zelenskiy. Instead, they say Democrats just want to undo the 2016 election. Republicans dismiss witness testimony of a shadow diplomacy being run by Trump lawyer Rudy Giuliani, and they rely on the president’s insistence that he was merely concerned about “corruption” in Ukraine — though the White House transcript of Trump’s phone call with Zelenskiy never mentions the word.

“They are trying to impeach President Trump because some unelected bureaucrats chafed at an elected President’s ‘outside the beltway’ approach to diplomacy,” according to the report from Republican Reps. Devin Nunes of California, Jim Jordan of Ohio and Michael McCaul of Texas.

Schiff said the GOP response was intended for an audience of one, Trump, whose actions are “outside the law and Constitution.”

Democrats could begin drafting articles of impeachment against the president in a matter of days, with voting in the Judiciary Committee next week.

Republicans on the committee, led by Rep. Doug Collins of Georgia, plan to use procedural moves to stall the process and portray the inquiry as unfair to the president.

The White House declined an invitation to participate, with counsel Pat Cipollone denouncing the proceedings as a “baseless and highly partisan inquiry” in a letter to Judiciary Chairman Jerrold Nadler, D-N.Y.

Trump had previously suggested that he might be willing to offer written testimony under certain conditions, though aides suggested they did not anticipate Democrats would ever agree to them.

Cipollone’s letter of nonparticipation applied only to the Wednesday hearing, and he demanded more information from Democrats on how they intended to conduct further hearings before Trump would decide whether to participate.

Nadler said Monday if the president really thought his call with Ukraine was “perfect,” as he repeatedly says, he would “provide exculpatory information that refutes the overwhelming evidence of his abuse of power.”

House rules provide the president and his attorneys the right to cross-examine witnesses and review evidence before the committee, but little ability to bring forward witnesses of their own.

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