Now the House Progressive-Democrats have deigned deliver their Articles of Impeachment to the Senate, and the Senate’s trial will begin in earnest (the Chief Justice of the Supreme Court has been sworn in, and the Senators have been sworn in) tomorrow right after lunch Eastern Time.  There remains speculation about whether the Senate will call additional witnesses in the course of the trial or whether the Senate should simply dismiss the case.

The matter seems clear to my august self.

Under our Constitution, the House has the sole responsibility to conduct an impeachment investigation and to produce the resulting Articles of Impeachment. Further, only the House is allowed to conduct that investigation. Finally, that investigation is entire and complete with the writing of the Articles. Art I, Sect 2:

The House of Representatives…shall have the sole Power of Impeachment.

Under our Constitution, the Senate has the sole responsibility to try the House’s impeachment Articles. Further, that’s all the Senate is allowed to do vis-a-vis impeachment. In particular, it cannot conduct its own investigation. Art I, Sect 3:

The Senate shall have the sole Power to try all Impeachments.

The Senate should hear the cases presented by the House’s and President’s impeachment managers, evaluate the case as presented in the Articles, and then vote to acquit or convict. No further investigation, no witnesses, nothing else at all is required or legitimate.