CBS News has obtained a letter from House Speaker Nancy Pelosi stating that the House will vote this week to make the impeachment inquiry formal. They will also establish a procedure for the ongoing House investigation.
House Representative Jim McGovern, the chairman of the House Rules Committee, released a statement Monday that says that the House of Representatives will "begin the public-facing phase of its impeachment inquiry into the conduct of President Donald Trump."
According to multiple reports, the House is expected to vote on the impeachment inquiry procedure on Thursday.
Representative McGovern went on to say in the statement, "I will be introducing a resolution to ensure transparency and provide a clear path forward, which the Rules Committee will mark up this week."
The House Rules Committee will meet Wednesday.
A former national security official defied a House subpoena Monday, escalating a standoff between Congress and the White House over who will testify in the impeachment inquiry against President Donald Trump.
Charles Kupperman, who was a deputy to former national security adviser John Bolton, failed to show up for a scheduled closed-door deposition after asking a federal court in Washington to rule on whether he was legally required to appear. In a statement, Kupperman said he was awaiting "judicial clarity."
House Intelligence Chairman Adam Schiff said Kupperman's suit has "no basis in law" and speculated that the White House didn't want him to testify because his testimony could be incriminating. Democrats are investigating Trump's pressure on the Ukrainian government to pursue politically motivated investigations as the administration was also withholding military aid to the country.
"If this witness had something to say that would be helpful to the White House they would've wanted him to come and testify," Schiff told reporters. "They plainly don't."
Schiff said the three committees leading the impeachment inquiry will move forward, with or without testimony from Kupperman and other witnesses. Democrats have indicated that they are likely to use no-show witnesses to write an article of impeachment against Trump for obstruction of justice, rather than launching potentially lengthy court battles to obtain testimony.
"We are not willing to allow the White House to engage us in a lengthy game of rope a dope in the courts, so we will move forward," Schiff said.
Schiff said over the weekend that he wants Bolton to testify, though that has not yet been scheduled. He told ABC's "This Week" on Sunday that Bolton, who according to other witnesses had concerns about the Ukraine policy, "has very relevant information." But he predicted that the White House, which has vowed to obstruct the investigation, would fight a Bolton appearance.
After hearing from a series of State Department officials, the three committees leading the impeachment investigation are turning their focus to the White House. Lawmakers say they are hoping to get more answers about what aides close to Trump knew about his orders on Ukraine policy.
"They're in the White House, so they're much closer to where the policymaking supposedly was supposed to happen with regard to the Ukraine, and they can really shine a light on whether it was happening properly or not," said Illinois Rep. Raja Krishnamoorthi, a Democratic member of the House intelligence panel.
Several of the State Department officials have already told lawmakers of their concerns as Trump's personal lawyer, Rudy Giuliani, took charge of Ukrainian policy and as Trump pushed out the U.S. ambassador there.
William Taylor , the current top diplomat in Ukraine, testified last week that he was told aid to the country would be withheld until the country conducted investigations into Democrat Joe Biden and his family and into Ukraine's involvement in the 2016 U.S. presidential election.
Democrats also want to hear from two current national security White House staffers, Alexander Vindman and Tim Morrison, who are scheduled to appear this week. It is unclear if they will do so following Kupperman's defiance of a subpoena.
In Kupperman's lawsuit, he asked a judge to decide whether he should accede to House demands for his testimony or to assert "immunity from congressional process" as directed by Trump. He said he "cannot satisfy the competing demands of both the legislative and executive branches," and without the court's help, he said, he would have to make the decision himself — one that could "inflict grave constitutional injury" on either Congress or the presidency.
"Given the issue of separation of powers in this matter, it would be reasonable and appropriate to expect that all parties would want judicial clarity," Kupperman said in a statement.
The court had yet to rule by Monday morning, and his lawyer said in a letter that he was waiting for a judge to step in before committing to testify.
The three chairmen of the House committees overseeing the inquiry told Kupperman's lawyers in a letter over the weekend that the suit was without merit and appeared to be coordinated with the White House. They called it "an obvious and desperate tactic by the President to delay and obstruct the lawful constitutional functions of Congress and conceal evidence about his conduct from the impeachment inquiry."
Kupperman's attorney, Charles Cooper, wrote in a letter it was not his client who was challenging Congress' constitutional claims.
"It is President Trump, and every president before him for at least the last half century, who have asserted testimonial immunity to their closest confidential advisers," Cooper wrote. "If your clients' position on the merits of this issue is correct, it will prevail in court, and Dr. Kupperman, I assure you again, will comply with the court's judgment."