WASHINGTON — President Trump on Sunday injected fresh instability into final preparations for the Senate’s impeachment trial, suggesting that senators should dismiss the House’s charges of high crimes and misdemeanors against him outright rather than dignifying them with a full tribunal.
That unexpected statement, arriving amid a flurry of tweets, not only appeared to put the president at odds with Republican Senate leaders moving toward a full trial but also contradicted Mr. Trump’s own words from just hours earlier, when he argued for a trial that would include as witnesses Democratic House leaders who are prosecuting him.
“Many believe that by the Senate giving credence to a trial based on the no evidence, no crime, read the transcripts, ‘no pressure’ Impeachment Hoax, rather than an outright dismissal, it gives the partisan Democrat Witch Hunt credibility that it otherwise does not have,” Mr. Trump wrote on Twitter on Sunday afternoon. “I agree!”
It was the latest instance of the president publicly vacillating between his apparent desire to make the charges disappear and to precipitate an extended spectacle in the Senate that would turn the tables and put his critics on trial. Hours before, Speaker Nancy Pelosi had warned that anything short of a full trial with new witnesses and evidence would abet Mr. Trump’s attempts to cover up wrongdoing.
As the subject of the charges on trial, Mr. Trump has no direct say over how the Senate proceeds and, by all accounts, Republicans do not have the votes needed to dismiss the case as Mr. Trump suggested, at least not before hearing opening arguments.
But the remarks could put lawmakers from his party in a difficult position in the weeks ahead if they have to justify to constituents loyal to the president why they are even giving a hearing to a case he derides as a “sham.”
And the zigzagging underscored the challenge facing Mr. Trump’s defense team and the Senate majority leader, Mitch McConnell of Kentucky, as they try to navigate competing interests just days before the trial is to begin. Mr. McConnell has said he intends to run a trial similar to the 1999 impeachment proceeding against President Bill Clinton, meaning both House prosecutors and Mr. Trump’s defense team will be given a chance to present their arguments.
Mr. Trump’s running impeachment commentary came on a day when much of Washington was busy preparing for the trial, only the third such proceeding in American history. Ms. Pelosi has said the House will send the two articles of impeachment charging Mr. Trump with abuse of power and obstruction of Congress sometime this week, with a trial commencing as soon as Wednesday.
Appearing Sunday on ABC’s “This Week” before Mr. Trump’s tweet, Ms. Pelosi told senators considering forgoing a full trial that “dismissing is a cover-up” and asserted that whatever the outcome, the trial could never “erase” the stain of impeachment from Mr. Trump’s record.
Even as the speaker expressed optimism that the House’s three-month impeachment inquiry had collected enough evidence to win a conviction on its two charges, she implicitly acknowledged the difficulty Democrats would have in doing so. And she warned that the Senate proceeding might be little more than a cover-up if Republican senators did not agree to summon new witnesses and documents that Mr. Trump blocked from the House.
“We have confidence in our case that it’s impeachable, and this president is impeached for life, regardless of any gamesmanship on the part of Mitch McConnell,” the speaker said, referring to Mr. McConnell.
The House impeached Mr. Trump last month on two counts related to what Democrats concluded was a campaign by the president to pressure Ukraine to investigate his domestic political rivals, including by withholding as leverage a White House meeting and nearly $400 million in vital military aid from the country.
“There’s nothing,” Ms. Pelosi said, “the Senate can do that can ever erase that.”
The comments appeared to be an acknowledgment that given the highly polarized state of the nation and the Senate, there was little chance that the two-thirds of senators needed for conviction and removal would agree to do so. They also foreshadowed a likely election-year strategy by Democrats, who are prepared to argue that voters should serve as an appeals court on Mr. Trump’s fitness for office.
“They take an oath to have a fair trial, and we think that would be with witnesses and documentation,” Ms. Pelosi said. “Now the ball is in their court to either do that, or pay a price for not doing it.”
Before he called for a dismissal of the case, Mr. Trump appeared to be piqued by Ms. Pelosi. He suggested on Twitter questions for Ms. Pelosi to answer on air and later responded to her statements about his legacy.
“Why should I have the stigma of Impeachment attached to my name when I did NOTHING wrong?” he asked in one tweet, after her appearance, adding, “Very unfair to tens of millions of voters!”
In other posts, Mr. Trump repeated familiar attacks on the speaker and Representative Adam B. Schiff, the California Democrat and House Intelligence Committee chairman who oversaw the impeachment inquiry and is likely to lead the prosecution in the Senate. Both Ms. Pelosi and Mr. Schiff, he said, ought to be witnesses during the impeachment trial, a common argument among Republicans who believe the two lawmakers have mishandled their duties in their conduct of the impeachment inquiry.
Congressional Republicans close to Mr. Trump also pounced on the speaker’s prediction, arguing that it betrayed the Democrats’ true motivation throughout the impeachment process: to build a case, any case, to slime Mr. Trump’s re-election campaign before the November election.
“Remember this, next time they try to pretend they were ‘prayerfully’ or ‘reluctantly’ impeaching @realDonaldTrump. They weren’t,” Representative Mark Meadows, Republican of North Carolina, wrote on Twitter. “It was all about trying to politically damage the President.”
Ms. Pelosi unexpectedly withheld the articles in a bid to increase pressure on Republican senators to commit to calling witnesses, without whom Democrats privately concede they have no shot of even coming close to a conviction. Though she relented without winning any commitments from Republicans, the speaker argued on Sunday that she had succeeded in showing the public “the need for witnesses.”
Republican senators have already challenged the speed and exhaustiveness of the House’s inquiry, and questions about the strength of the evidence it gathered and witnesses it did not secure are likely to be front and center as the trial gets underway.
Under the rules Mr. McConnell intends to adopt, senators will eventually be able to vote on whether to call witnesses or other evidence, but there is no guarantee they will do so. Mr. McConnell has made clear that he wants a narrow and speedy trial, and that he does not foresee any chance of a conviction.
It would take only four Republican senators to break ranks and join Democrats to secure the majority needed to compel the new testimony — though even that may not be a guarantee.
“I don’t expect anything, but I don’t think it’s impossible,” said Senator Michael Bennet of Colorado, who is seeking the Democratic presidential nomination to take on Mr. Trump this fall, when asked about possible Republican defections.
The most animated witness fight may be over John R. Bolton, the former White House national security adviser who said last week that he would be willing to testify in the trial if called by the Senate and even if the White House ordered him not to. Other impeachment witnesses and people close to him say that Mr. Bolton was deeply alarmed by Mr. Trump’s actions toward Ukraine and, as one of his top aides, has relevant, firsthand information to share with lawmakers.
Ms. Pelosi said on Sunday that she had not “excluded” the possibility that the House could subpoena Mr. Bolton to testify, but indicated that it was the Senate’s responsibility for now. Mr. Schiff agreed, saying that there was “little sense” in bringing Mr. Bolton into the House now.