Chief Justice John Roberts swears in senators for impeachment trial

After being sworn in by Sen. Chuck Grassley (R-Iowa) on Thursday, Supreme Court Chief Justice John Roberts administered an oath for all senators to deliver "impartial justice" in the impeachment trial of President Trump.

Why it matters: The ceremony kicks off a period in which senators will not be permitted to speak to each other or bring electronic devices onto the Senate floor.

• Several Republican senators, including Majority Leader Mitch McConnell (R-Ky.) and Lindsey Graham (R-S.C.), have sparked controversy by stating that they will not be impartial jurors.
• McConnell will recess the substantive part of the trial — opening arguments and the Q&A period — until Tuesday in order to give House managers and Trump's defense team a few days to prepare.

What they're saying: The oath, which dates back to the 1700s, reads: “I solemnly swear that in all things appertaining to the trial of the impeachment of Donald John Trump, president of the United States, now pending, I will do impartial justice according to the Constitution and laws: So help me God."

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