As folks are saying, if that's the defence, you know they are in trouble.
The argument seems to be that you cannot trust the whistleblower's document complaining about Trump's call with the Ukrainian president and saying that the record of it had been concealed on a secure server because he heard it second hand.
This is the sort of argument you might make when the evidence doesn't exist from eye witnesses supporting the complaint.
But here, of course, it does: we have a transcript of the call, which was published by the president, and which reflects exactly the one the whistleblower alleged had occurred (with one or two ellipses); and we have an admission by the White House that it moved this transcript onto a secret server.
Those are the two key allegations the whistleblower made and it is known his second hand account accurately reported the history.
And yet Lindsey Graham, a person in a position of authority in the US senate's Judiciary Committee, has indicated that his objection to this matter is that it is based on hearsay.
Doh! He must think Republicans are such rubes if he thinks that line is going to hold.