Michael Lowry has accused the Moriarty Tribunal of operating under a false guise.
The independent TD has broken his 10-year-silence on the inquiry in an article in the Sunday Tribune in which he raises questions of the inquiry's impartiality.
He was commenting on the tribunal's inquiries this week which deal with the awarding of the State's second mobile-phone licence to businessman Denis O'Brien.
Mr O'Brien accused the tribunal of an organised conspiracy.
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