Roberts should not be presiding over this case. He created appointed the FISA court judges which are in question.
This is the process set up in our government. Much like a jury in our civil/criminal courts.
This is our government process and it needs to work itseld out. If the President
is cleared and hasn’t borken the laws then he will be cleared.
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Impeachment in the United States is the process by which a legislature
(usually in the form of the lower house) brings charges against a
civil officer of government for crimes alleged to have been committed,
analogous to the bringing of an indictment by a grand jury.
Most impeachments have concerned alleged crimes committed while in office,
though there have been a few cases in which officials have been impeached
and subsequently convicted for crimes committed prior to taking office.
The impeached official remains in office until a trial is held. That trial,
and removal from office if convicted, is separate from the act of impeachment itself.
In impeachment proceedings, the defendant does not risk forfeiture of life,
liberty, or property. According to the Constitution, the only penalties allowed
to be imposed by the Senate are removal from office and disqualification from
holding any federal office in the future.
https://en.wikipedia.org/wiki/Impeachment_in_the_United_States