There is no whistleblower.
Only second-hand knowledge.
A court of law would reject as non-factual.
I believe this is a pure legal argument to protect the source (the second-hand hearsay witness).
A whistleblower, one who has first-hand knowledge of an event, would expose himself to criminal prosecution if he lied.
A whistleblower who does not know any facts, but just second-hand information, is much less likely to be criminally prosecuted as he could always say he was told what the facts are by others, so they are the ones that lied.
The critical component here is adherence to centuries-old definition of what is fact and what is not. The Dems are portraying a whistleblower with second-hand knowledge as comparable to one with first-hand knowledge. If they get away with that, they are much less likely to be prosecuted when the truth finally shows up/
