Lawyers for TD Liam Lawlor have accused the Flood Tribunal of being "oppressive".
Counsel for Deputy Lawlor, John Rogers, said on one occasion, Justice Fergus Flood instructed his client to sign a piece of paper while in the witness stand.
This was done without a court order, he added, and constituted an "oppressive" action. Deputy Lawlor's legal team is maintaining its argument at the High Court that questions about his business affairs abroad have nothing to do with planning in Dublin.
The Dublin West TD could face a term in jail if he is found to be in contempt of a court order issued last October.