I want to know why you think that? I have 30+ years in courtrooms and I come to this with a bit more experience.
Many have no idea what’s going on, and no way to discern.
The call has been transcripts on TV. THE COMPLAINT. What I saw was a choice of privacy that included 46 fully engaged Republican house members asking questions just like Democrats.
No defendant participates in Grand jury testimony. They keep it private. A sound rule for sound reasons.
Witnesses testifying without knowing what others said, are historically more likely to tell the truth. Conversely handing prospective witnesses transcripts to study first can only currupt the truth finding. Which has to be the assumed motive.
Calling witnesses about Biden, confuses an impeachment proceeding of Trump.
Sure, great defense, as is anything confusing, prejudicial and of no probative value. That is precisely the defenses goal.
Ultimately, these are administration witnesses. Subject to discipline and retribution from their employer.
The GOP house members have an advantage, as they have access, to information before it is published in a depo.
Finally, once complete, there will be a public hearing. With cross.