Trump never said anything advocating violence or breaking the law during the demonstration. In fact, he specifically said NOT to do that. So disproving that part of the incitement claim is easy.
The other part of the incitement claim is that he got people really riled up and mad by claiming the election was stolen, and some of those people might have participated in the illegal Capitol activities. This leaves aside for the moment the possibility that left wing goons pretending to be Trump supporters were among the people that actually incited illegality.
In a country with the FIrst Amendment , speaking the TRUTH In the political arena, however shocking it is or likely to stir up people, cannot and should not ever be criminalized or punished by the government . Otherwise there is no freedom or speech if the powers that be can prohibit saying things they don’t like even if they are true. Freedom of political speech is deemed important enough that it protects false political statements so there can be robust political debate.
Freedom of speech is not absolute. Yelling “Fire” in a crowded theater that leads to a stampede is not protected free speech. But if there really was a fire, the person who yelled “fire” surely cannot be punished if somebody gets hurt trying to escape, under any sensible understanding of the First Amendment
If Trumps claim of election theft is TRUE, that cannot be considered a high crime or misdemeanor. If it is, the First Amendment is a sham.
If TRUTH is an absolute defense to these charges, and if Trump is prohibited from making his defense, that is a violation of his due process rights. He should walk out while on national TV and explain why he is doing so.
I hope Trump intends to argue something like this. If the Senate does not allow Trump to defend himself , the Senate will go down in history as an institution no better than the Star Chamber or courts in countries like the Soviet Union that held show trials with a pre-determined “guilty”outcomes.
The “TRUTH” means ABSOLUTELY nothing to these people. They kill babies and call it “freedom”.