The Trump administration’s ill-conceived blatant defiance of congressional demands for the testimony of State Department witnesses and documents in its ongoing impeachment inquiry into the Ukraine scandal has dramatically increased the likelihood that the president will be impeached.

Donald Trump's lawless flouting of the Constitution adds an independent ground for his impeachment to the questions already being investigated, and the collateral damage to other administration officials is the real prospect of criminal prosecution for obstructing a congressional investigation — though such a prosecution would have to be pursued by a future Justice Department.

The latest example of presidential stonewalling occurred Tuesday when Gordon Sondland, the U.S. ambassador to the European Union whose text messages have revealed his deep personal involvement in the administration’s efforts to press Ukraine President Volodymyr Zelenskiy to investigate Joe Biden and his son, abruptly refused to testify. During the night, administration officials had ordered Sondland not to appear; Sondland also passed documents sought by Congress to the State Department, where they remain hidden.

The White House’s intransigence further flared late Tuesday in a caustic and meandering 8-page letter from White House counsel Pat Cipollone to House committee chairmen declaring that no administration officials will appear to testify or provide documents sought in the impeachment inquiry, claiming that the entire process is unconstitutional and a violation of due process, among other poorly-sourced legal and primarily political arguments.

The House Democrats’ immediate and blunt response was the issuance of a subpoena for Sondland to produce documents and give his deposition Oct. 16.

The White House is on thin ice. The words of the Constitution, the history of prior American impeachments, the adoption in 1974 by the House Judiciary Committee of Article III of impeachment against President Richard Nixon and a 1993 ruling of the U.S. Supreme Court refute the legitimacy of the White House’s battle plan to interfere with impeachment proceedings.

The Constitution, for one, vests the “sole power of impeachment” in the House of Representatives and, in an impeachment proceeding, it has the wide-ranging ability to demand both documents and testimony.

In its 1974 final report in the impeachment of Nixon, the Judiciary Committee described the sweeping breadth of congressional impeachment power to require testimony and documents from the executive branch. For instance, when President James Polk in 1846 declined to provide information to a House committee in a legislative investigation, he “cheerfully admitted” the House’s sweeping power to investigate during an impeachment inquiry, the report stated.

Polk wrote that “the power of the House in the pursuit of this object [impeachment] would penetrate into the most secret recesses of the Executive Departments. It could command the attendance of any and every agent of the Government, and compel them to produce all papers, public or private, official or unofficial and to testify on oath to all facts within their knowledge.”

This actually occurred in the 1867 impeachment proceedings of President Andrew Johnson: “Cabinet officers and presidential aides were questioned in detail about Cabinet meetings and private conversations with the President;” “[w]itnesses answered detailed questions on the opinions of the President, statements made by the President, and advice given to the President,” the 1974 report explained.

Nixon, for his part, famously refused to comply with Judiciary Committee subpoenas for White House tapes. In the immediate aftermath, the committee rejected a motion to recommend that the House hold Nixon in contempt because the consequences of his stonewalling demanded a more serious response: impeachment.

The Supreme Court, too, rejected the president’s executive privilege claim in ruling 8-0 that Nixon had to produce White House tapes in response to a subpoena in a criminal trial.

During the debate over whether the committee should adopt Article III — impeaching Nixon for interfering with the House’s sole power of impeachment by defying committee subpoenas — Rep. Robert McClory, R-Ill., spoke eloquently in favor of its adoption. “We have this challenge on the part of the Executive with respect to our authority,” he said. “And if we think of the whole process of impeachment, let us recognize that this is a power which is preeminent, which makes the Congress of the United States dominant.”

“It bridges the separation of powers and gives us and reposes in us the responsibility to fulfill this mission,” he added. “And the only way we can do it is through acting favorably on Article III.”

McClory predicted that, if a future president were subject to impeachment, adopting Article III would be a “precedent that we might establish here [that] would be effective then.” McClory and another Republican then joined 19 Democrats in adopting Article III.

History aside, Cipollone’s central legal claim that the current impeachment inquiry denies Trump due process is too specious to be overlooked. Even an essay by Stephen Presser in the conservative Heritage Foundation’s “Guide to the Constitution” states: “The appropriate place of bringing charges of impeachment, which power is analogous to the bringing of criminal charges by a grand jury, is in the lower house of the legislature. Just as the grand and petit juries are popular institutions, so it made sense to have the branch closest to the people charged with this indictment-like power.”

Exactly so. And like a grand jury, witnesses are not entitled to be accompanied by counsel when they testify, and the subject’s lawyers have no right to attend.

Beyond that, the law is clear that the judicial branch cannot and will not interfere in the legislative branch’s impeachment prerogatives. In 1993, the Supreme Court unanimously ruled that an impeached and convicted federal judge Walter Nixon could not challenge in court the Senate trial removing him.

Chief Justice William Rehnquist referred to the constitutional language giving the House the “sole” power to impeach and the Senate the “sole” power to try the articles of impeachment, writing: “The common sense meaning of the word ‘sole’ is that the Senate alone shall have the authority to determine if an individual should be acquitted or convicted.” The court ruled that the Senate’s conduct could not be reviewed by the courts as it is a “political question.”

Similarly, the House impeachment procedures are established in its sole discretion and may not be challenged on any basis in court.

The text of the Constitution and history will doom Trump’s flailing effort to escape the consequences of his actions. The House will do its duty, likely giving 100 senators a vote that will determine how each will be viewed by history — and his or her constituents in the elections to come.