The Oireachtas Committee investigating the behaviour of Judge Brian Curtin agreed to pay his costs after hearing it was likely that a refusal by them would have led to a further High Court challenge which the judge could have won.
Committee chairman Denis O'Donovan (FF) said they had made the decision "having analysed the very strong submission made by Judge Curtin's legal team and having taken our own advice from senior counsel".
After a special sitting on Wednesday to deal with costs, "we felt we had no option but to award costs and that was agreed, subject to those costs being reasonable of course", he told RTÉ radio's Morning Ireland yesterday.
He said the estimates that this could involve a bill of €1 million were "totally speculative" but admitted it was possible. "We absolutely don't know because we don't know how long the process will take." He hoped to be able to "report progress" by the end of July, "but that is somewhat speculative".
Even after his committee has completed its work, it is then up to the Oireachtas to decide whether to take action to dismiss him.
Judge Curtin was acquitted on charges of having child pornography in 2004 after it emerged that a warrant used by gardaí to seize his computer was out of date.
Mr O'Donovan said yesterday that two computer experts, one retained by the committee and the other by Judge Curtin, would now be involved in the handover of the computer from the Garda authorities, who have it, to the committee.
"That can be done in a matter of weeks rather than months," he said.
The computer experts would then take a "mirror image" of the computer's hard drive and examine it to see if, as alleged, it contained images of child pornography.