Nancy Pelosi has rebuffed pressure to initiate an impeachment inquiry by arguing that there are other means of holding President Trump accountable for his corruption and wrongdoing — a goal that the House speaker herself has cast as imperative for protecting our democracy.

“We all firmly agree that we should proceed down a path of finding the truth,” the House speaker recently wrote in a letter to House Democrats. “It is also important to know that the facts regarding holding the President accountable can be gained outside of impeachment hearings.”

That’s true. But what happens if the White House will not allow Congress to get access to the “facts” that are necessary to carry out the task of “holding the President accountable”?

Trump, in a new interview with The Post, just made it overwhelmingly clear that he will henceforth treat the House and its reasonable oversight efforts as fundamentally illegitimate.

“There is no reason to go any further, and especially in Congress where it’s very partisan — obviously very partisan,” Trump said, referring to the latest round of oversight requests House Democrats have made.

Trump’s justification: The White House already fully cooperated with special counsel Robert S. Mueller III’s investigation (Trump actually refused to testify and tried to get Mueller fired), so there’s no reason to cooperate “any further” with Congress.

Former Democratic presidential candidate calls for Congress to be "deliberate, fair and fearless." (Danielle Kunitz, Kate Woodsome, Joshua Carroll/The Washington Post)

Thus, the Treasury Department just informed House Democrats that it will not meet the deadline of their request for Trump’s tax returns. While it’s still possible that this could change, this looks extremely unlikely, as long as Trump does not want his returns disclosed, which he adamantly does not.

Meanwhile, the White House is preparing to lean on former White House counsel Donald McGahn to defy a subpoena to testify before the House Judiciary Committee, to elaborate on the extensive testimony he gave to Mueller supporting the case that Trump obstructed justice. The White House may assert executive privilege.

But here’s the thing: If the White House continues down this path, it will make it still harder for House Democrats to resist an impeachment inquiry. Because if they launch one, their legal case for doing things such as compelling McGahn’s testimony and getting Trump’s returns will get even stronger than it already is.

Impeachment inquiry could strengthen Democrats’ hand

In requesting the last six years of Trump’s personal and business tax returns, Rep. Richard Neal (D-Mass.), the chairman of the Ways and Means Committee, noted that Congress needs them to conduct oversight into whether the IRS is auditing and enforcing tax laws against the president, and to inform relevant legislation.

The legal case for getting Trump’s returns is already strong. If a tax-writing committee requests an individual’s tax returns — say, those of Individual-1 — then the Treasury Department “shall” furnish them. Neal additionally provided a legislative purpose.

In rebuffing this request, Treasury Secretary Steven Mnuchin argued that this legislative purpose was a sham. Mnuchin said the returns must be “pertinent” to an inquiry that is “within the jurisdiction of the committee” and furthers a “legitimate task of the Congress.”

In saying this, Mnuchin actually revealed that an impeachment inquiry — which would constitute a legitimate congressional task — would strengthen that case, legal experts tell me.

“The response is that this request doesn’t relate to a legitimate inquiry,” Randall Eliason, who teaches white-collar crime law at George Washington University, told me. “If you had an impeachment hearing underway, and the focus was whether the president has financial conflicts or ties with foreign powers that are influencing his policies or compromising him in some way, then his tax returns become very relevant.”

This is also the case when it comes to McGahn’s testimony, legal experts say.

Georgetown Law professor Joshua Matz, who co-wrote a good book on impeachment with law professor Laurence Tribe, told me that the House’s oversight role already provides a strong basis for subpoenaing McGahn. But if the White House asserts executive privilege, Matz said, an impeachment inquiry would constitute an even more powerful case for the courts to override it.

“There’s no doubt that the President has an important, legitimate interest in executive privilege,” Matz told me. “But in our constitutional structure, the impeachment power is mightier and more fundamental than virtually any interest that the President might raise against it.”

McGahn provided granular dramatization of Trump’s obstruction. Among other things, he recounted that Trump ordered him to fire Mueller, then directed McGahn to lie about it and create a paper trail covering it up.

Obstruction of justice has historically been an impeachable offense, confirming, as Adam Liptak puts it, that the “Constitution cannot tolerate” the “corrupt use of power to frustrate lawful investigations,” because this threatens “the constitutional order.”

Mueller did not indict, as per Justice Department policy. But his report identified repeated cases of obstructive conduct that Trump undertook with improper intent, especially including those involving McGahn.

The case for launching an impeachment inquiry is already strong based on what we know. If Democrats want to take intermediate steps like hearing from McGahn first, but the White House blocks them, an impeachment inquiry would then be the last resort — for sound structural reasons.

“The entire premise of the impeachment power is that in truly extreme cases of wrongdoing, Congress is our ultimate check on a rogue president,” Matz told me. “In carrying out this mandate, Congress has near-unlimited authority to engage in whatever fact-finding it deems necessary.”

A dilemma for Democrats

Perhaps Trump views an impeachment inquiry as a less bad outcome than releasing his tax returns. Or perhaps he hopes to run out the clock, gambling that Democrats won’t have the guts to pull the trigger.

If so, that creates a torturous dilemma. Democrats themselves say the full truth must be pursued, for the sake of the country. But if Trump blocks them from doing that, it would seem to force their hand and require an impeachment inquiry.

It really might come down to a choice between that and allowing Trump to neuter them entirely, in a way that — by their own lights — puts the country and the rule of law in extreme peril.

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