An Independent TD said members of the Dáil are "outraged" at the legal action Denis O'Brien is taking against the State.
Mr O'Brien claims that the Dáil disciplinary committee failed to take action against Catherine Murphy for what he deems an abuse of parliamentary privilege.
He has begun legal action against the committee members.
"I know the amount of people that I've spoken to, other TDs I've spoken to, are outraged, to be quite frank, that he would take that line," Deputy Halligan, a member of the committee, said of the reaction so far.
"For what purpose [he did], I don't know."
He claimed the action is an effort to stifle members of the Oireachtas, and said that no-one in a position of authority should be trying to influence the Dáil.
And, he said, the committee could note make a ruling on Catherine Murphy's original comments as they don't know if they were true or not.
"The position we found ourselves on the CPP was that we couldn't say if what Catherine Murphy said was correct or incorrect. We weren't in a position to censor [her].
"It's disappointing and surprising that Denis O'Brien would in some way believe that the CPP should have acted in defence of himself, on something … we cannot be sure is true or untrue."