@metal-brain said
"The majority rejected the premise that a Senator was a "civil officer of the United States" and the same majority, by an identical 14-11 vote, then decided the Senate did not have jurisdiction to impeach."
What is your source of information?
The article.
Read it.
EDIT: Here I'll help:
"In January of 1799, after three days of exhaustive arguments, the Senate deliberated behind closed doors, then voted on two resolutions. On January 10, 1799, the Senate failed to pass the following resolution by a vote of 11–14:
That William Blount was a civil officer of the United States within the meaning of the Constitution of the United States, and therefore liable to be impeached by the House of Representatives; That as the articles of impeachment charge him with high crimes and misdemeanors, supposed to have been committed while he was a Senator of the United States, his plea [to dismiss the charges] ought to be overruled.
On January 11, 1799, the Senate approved the following resolution by a vote of 14–11:
The court is of opinion that
the matter alleged in the plea of the defendant is sufficient in law to show that this court ought not to hold jurisdiction of the said impeachment, and that the said impeachment is dismissed."
So the Senate rejected the idea that a Senator was "a civil officer of the United States within the meaning of the Constitution of the United States," and thus could not be impeached. It said nothing about the claim that he could not be impeached because he had already resigned and the majority in Belknap rejected that idea.