The Mahon Tribunal has heard that the question of tax designation for the Blanchardstown shopping centre was ruled out by the Government in 1990.
The inquiry is investigating an allegation that Taoiseach Bertie Ahern received £30,000 in around 1993 to block the incentive for the west Dublin development.
Department of Finance official Liam Murphy testified that his department was always opposed to extending urban renewal tax breaks to suburban green field developments.
He said a special case had been made for the Tallaght Shopping Centre in 1989 as the area had a population nearly the size of Limerick and 'had nothing' in the way of facilities.
Mr Murphy said there was then pressure to extend the tax break to Blanchardstown centre as its developers argued they were facing unfair competition.
Then Environment Minister Padraig Flynn had supported this extension in 1989.
But Mr Murphy agreed with tribunal counsel that the final decision was with the Department of Finance who were always opposed to it.
He agreed that according to memos the Department of Environment officials themselves ruled out support for the Blanchardstown tax break in 1990.
