House Speaker Nancy Pelosi, D-Calif., says she plans to send the articles of impeachment to the Senate next week, despite her ongoing concerns over how Republicans plan to conduct the Senate trial.

Pelosi plans to move ahead by transmitting the articles and naming impeachment managers who will present the House case in the Senate trial. She said in a letter to House Democrats that she would consult with the caucus on Tuesday about next steps.

"In an impeachment trial, every Senator takes an oath to 'do impartial justice according to the Constitution and laws.' Every Senator now faces a choice: to be loyal to the President or the Constitution," Pelosi said in the letter.

Asked whether she thought the Senate trial would be "fair," she said no.

Before opening arguments, the Senate still needs to pass a resolution on the trial rules and send a summons to President Trump.

Senate Majority Leader Mitch McConnell, R-Ky., has so far refused to reveal the details of how he plans to mange the trial, including how long it will take to start the trial after Pelosi releases the articles. He announced earlier this week that Senate Republicans have the votes to approve rules for the trial without the help of Democrats, but he gave few specifics about what that rule would include.

McConnell has said he plans to follow the general outline established in the 1999 trial of former President Bill Clinton. Those rules, which were approved unanimously in the Senate, gave the House impeachment managers and the president's lawyers each 24 hours of floor time to argue their case. Senators then had 16 hours to ask questions — all before they could vote on calling new witnesses or submitting new evidence into the record.

"The Senate has a unanimous bipartisan precedent for when to handle mid-trial questions such as witnesses — in the middle of the trial," McConnell said Monday. "That was good enough for President Clinton, so it ought to be good enough for President Trump. Fair is fair."

Democrats say the Clinton comparison does not apply to Trump. At the time, Senators were considering re-calling witnesses who had already testified in the House. Democrats now want to call four witnesses, including former national security adviser John Bolton and acting White House Chief of Staff Mick Mulvaney, who the White House blocked from participating in the House investigation.

Pelosi rejects that argument.

"Feebly, feebly, the Majority Leader has said this is just like Clinton," Pelosi told reporters on Thursday. "It's exactly not like Clinton in that he won't do a bipartisan agreement on how to proceed. So, that's very important. But, it's not incidental to say but for the documentation and witnesses."

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