I have not seen what the rules are for a chairman conducting an investigation. I know Schiff complained about Nunes contacts with witnesses. But is it really a basis to disqualify, or just a political talking point? Congressional committees and hearings are totally different from courts of law.
dunno..check this thread - might get answers..
“So, is subornation by a committee chair of perjured testimony before that committee a felony?
If the chair is a Republican........yes”
https://www.freerepublic.com/focus/news/3733098/posts?page=7#7