It just dawned on me. (Senate trial)

[unblock]

34. That is not the case for the sort of questions we are talking about

Yes, the constitution spells out the high-level structure of the impeachment and trial process, such as the number of votes required for removal.

But it doesn't go into rules of evidence or whether irrelevant or immaterial matters can be discussed. Such as whether the defense can use the trial as an opportunity to smear a political opponent.

The construction says the Chief Justice "presides", but it doesn't specify any particular powers to go along with that. Moreover, the constitution also states that the power to conduct a trial belongs solely to the senate.

In any event, the trial will be held in accordance with the rules of the senate, which are always subject to change by the senate. They can't overrule the constitution for things like what's needed for a quorum or removal, but they can certainly say that Donnie and his lawyers can bring "evidence" to try to smear Biden.