Lawyers for the Moriarty Tribunal say a crucial witness will have to be brought back in the middle of next year if they have to replace Michael McDowell as their counsel.
Businessmen Denis O'Brien and Dermot Desmond have mounted a legal challenge to the Tribunal's decision to retain the former Tánaiste to cross-examine a crucial witness.
The Moriarty Tribunal is investigating the awarding of the country's second mobile phone licence to Esat Digifone, of which O'Brien and Desmond were shareholders.
Their lawyers are objecting to the Tribunal's hiring of former Attorney General McDowell claiming it gives the appearance of bias.
The Tribunal's lawyers today dismissed the allegation saying it cannot apply to the former PD leader as he will have no role of any kind in the decision-making process.
They also say that if the tribunal has to replace Mr McDowell as their lawyer, they will have to wait until the middle of next year to bring back a crucial witness for questioning.