THE legal eagle behind the successful challenge to the Government's information campaign is none other than the Labour party's legal adviser.
Labour leader Eamon Gilmore defended Richard Humphreys' role in representing Dublin-based engineer Mark McCrystal in his successful challenge to the Government's campaign.
"Richard Humphreys is a Labour party councillor. He's a barrister. The Labour party does not influence in any way the work of any member of the Labour party who is a lawyer," he said.
It also emerged that Mr McCrystal has gone to court over at least one other vote -- but that time he was unsuccessful.
In 2011, Mr McCrystal (42), of Kilbarrack, Dublin, then with a Lucan address, attempted, along with two others, to injunct the referendums on judges' pay and Oireachtas inquiries.
Following his successful appeal, Mr McCrystal insisted he had taken the action "in the interest of the Irish people" and stood to make "no personal gain" from the outcome.
However, speaking to Joe Duffy on RTE's Liveline, he refused to give any details about his private life or whether he had children himself.
He confirmed he was an electrical, mechanical and electronic engineer and said he was not a member of any political party. On the question of the funding of his legal action, Mr McCrystal said it had been undertaken on a pro bono basis.