The Morris Tribunal today began High Court proceedings to compel Detective Sergeant John White to appear before the tribunal.
A consultant psychiatrist for the suspended senior officer said he was unequivocally unfit to give evidence at the resumed hearings into garda corruption.
Barrister Eoin Lawlor, for Det Sgt White, made an application to the tribunal that all evidence on his client's medical condition be heard in private.
He said the suspended garda had a constitutional right to privacy and the publication of his medical concerns would further damage his health.
Justice Morris said he could only grant such an application if hearing the evidence in public constituted a risk to state security or put in jeopardy a criminal trial.
Consultant psychiatrist Dr Louis O'Carroll told Justice Morris that Det Sgt White had now withdrawn his consent for the medic to discuss his condition, unless it was in private.
Justice Morris adjourned the hearing briefly to consider his decision before announcing the tribunal would go to the High Court under section 4, of the Tribunals of Inquiry (Evidence) Acts, to compel the suspended officer to comply with its orders. "I've searched and I've been unable to find any reason why Sgt White is not in a position to answer the summons," Justice Morris said.
"I'm at a loss to understand how he can give instructions to his counsel and solicitor and directions to his doctor and then on the other hand be incapable of attempting to give straightforward evidence."
He added: "As far as I can see Det Sgt White is using his best endeavours to ensure that the tribunal is deprived of his evidence."
The tribunal is continuing with evidence on the detention of Roisin McConnell, who was arrested in December 4, 1996, in connection with the death of cattle dealer Richie Barron.
Mr Barron was later found to have died as a result of a hit-and-run collision. The botched probe into his death ultimately led to the tribunal and the unravelling of a web of corruption within the force.