Editorial: Trump flirts with impeachment if he threatens Mueller

President Trump made it clear from the get-go that he regards the Russia investigation being conducted by special counsel Robert S. Mueller III as a “witch hunt,� an absurd allegation that even his own nominee to head the FBI has rejected.

But this week, the president escalated his efforts to preemptively discredit the special counsel. There also have been disturbing reports of discussions in the White House about how Mueller’s investigation might be attacked or even aborted.

In a jaw-dropping interview with the New York Times, Trump criticized Mueller for accepting the special counsel’s post after being interviewed for the position of FBI director in the Trump administration and accused him of other unspecified “conflicts.�

More ominously, he warned that Mueller would be committing a “violation� if he investigated the financial affairs of the president or his family in matters “unrelated to Russia.� Asked whether he would fire Mueller if he pursued such matters anyway, Trump replied: “I can’t answer that question because I don’t think it’s going to happen.�

That sounds to us like a thinly veiled threat, considering that Trump fired former FBI director James Comey at least in part because of his work on the Russia investigation. It also betrays Trump’s misunderstanding of — or wishful thinking about — Mueller’s authority. Deputy Atty. Gen. Rod Rosenstein charged Mueller with investigating not only “any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump� but also “any matters that arose or may arise directly from the investigation.� That’s a broad charter, and an appropriate one.

But Trump’s comments are just part of a campaign the White House apparently is developing to discredit Mueller and his investigation. Several news organizations reported this week that White House lawyers have been researching the personal and political backgrounds of Mueller’s investigators in an attempt to prove they are biased. The president’s defenders already have complained that some members of Mueller’s team contributed to Democratic political candidates in the past. This is a distraction. The Justice Department has detailed rules governing conflicts of interest, and they don’t define political contributions as constituting a conflict.

Finally, the Washington Post reported Thursday that Trump has asked his advisors about his authority to grant pardons to aides, family members and even himself in connection with Mueller’s investigation. Any use of the pardon power to end or obstruct Mueller’s investigation would be an abuse of power and would provide legitimate grounds for impeachment.

As difficult as it may be for Trump, the president has to realize that continuing to interfere with Mueller’s investigation is outrageous and not within his authority. Impeachment already has become a real possibility that can’t be shrugged off and ignored. Each of Trump’s irresponsible bits of behavior and seeming threats to obstruct justice are adding to the bill of particulars that lawmakers eventually could draw up.

John Dowd, one of the president’s attorneys, said the Post’s pardon story was “nonsense� and “not true� and insisted that the president’s lawyers were cooperating with the special counsel. That’s reassuring, although it sounds disturbingly like the standard administration cry of “fake news� in response to unflattering stories. If the White House wants to be more credible on this issue, the president and his staff must stop casting aspersions on Mueller and his team, allow the investigation to run its course and retire the term “witch hunt� once and for all.

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