Former Fine Gael TD and Senator Liam Cosgrave has been given permission by the High Court to challenge his prosecution on corruption charges.
Mr Cosgrave is due to stand trial in October.
He is charged with receiving corrupt payments between 1992 and 1997 in relation to the rezoning of land at Carrickmines in Co Dublin.
The High Court was told that the principal witness in the trial will be Frank Dunlop.
Senior Counsel Brendan Grehan told the court that Mr Cosgrave had been prosecuted in 2005 for failing to declare a political donation, had pleaded guilty and been sentenced to community service.
But Mr Grehan said that statements made by Mr Dunlop in 2004 on the basis of which Mr Cosgrave was now being charged were available to gardaí in 2005 and were not disclosed to Mr Cosgrave's lawyers at that time.
He is claiming his new prosecution is an abuse of process.
The case will be back before the court on 29 March.