It wasn't a trial.
Biological/material claims require biological/material evidence, not stories.
It was a hearing, where eye witness testimony (which apparently involved first hand testimony) was given
in addition to other forms of evidence. What that is, people speculate documents, pictures, videos, etc.
Once again eye witness testimony is evidence. Can't believe I have to type that out
Whatever that evidence is, and we don't know because it was given in closed door testimony due to it being Classified, we now have Senate Majority leader Chuck Schumer on board with very specific language in a bipartisan bill about disclosure