Impeachment hearings are a joke and always favor the defendant. They are political show trials where you always get a split “jury” and the guilty/not guilty vote is just a referendum on whether you still support the president. Grassley could (and may) produce tapes of Biden with the Burisma CEO directing payments for getting Shokin fired, and he will retain not guilty verdicts of practically every Senate Democrat in an impeachment hearing.
In a criminal trial, the jury pool and outcome is much more of a crapshoot.
My bad.
I wrote "impeachment" but was thinking Mueller. The way the Trump's special counsel attorneys kept Trump from being indicted for a process crime -- the entire point of the investigation -- was sterling work.