Opus Dei feared its Irish members could face a backlash in the wake of the scandal over paedophile priest Fr Brendan Smyth and delays over his extradition to Northern Ireland in 1994.
The Irish head of Opus Dei raised concerns over potential discrimination after senior government officials had been questioned about their possible membership of the organisation.
Former attorney general Harry Whelehan resigned as president of the High Court following the delays in extraditing Fr Smyth.
It ultimately helped bring down the Fianna Fáil-Labour government of taoiseach Albert Reynolds after just two years, ushering in the “Rainbow Coalition” under taoiseach John Bruton.
Files released as part of the State Papers revealed the November 1994 scandal had repercussions outside of the political world.
Questions had been raised over whether individuals involved in the handling of the Fr Smyth case had been members of Opus Dei.
Regional vicar of Opus Dei in Ireland, Monsignor Dónal Ó Cuilleanáin, wrote to the new attorney general Dermot Gleeson on March 1, 1995, to express concern about statements that had been made a short time previously at the Oireachtas Committee on Legislation and Security.
The letter was copied to Mr Bruton, as well as Cardinal Cahal Daly, and the Archbishop of Dublin, Desmond Connell.
Msgr Ó Cuilleanáin said the Oireachtas proceedings had “given rise to a widespread perception that candidates for public office may properly be asked (in a discriminatory sense) whether or not they are members of Opus Dei”.
He said it had also been suggested that membership of Opus Dei might impair the discharge of the duties of such office.
“Such perceptions misjudge the true character of Opus Dei and, if acted on, would violate fundamental constitutional rights,” he added.
The monsignor said the purpose of Opus Dei was “purely spiritual and apostolic”, adding: “It is not a private association with a social or political agenda, much less a clandestine society.”
He also pointed out that it did not and could not involve itself in the professional, social or political decisions of its members.
Papal nuncio to Ireland, Emanuele Gerada, contacted the top civil servant in the Department of Foreign Affairs, Noel Dorr, two weeks later to see if he could “allay the fears” of Msgr Ó Cuilleanáin.
Mr Dorr noted in a memo that the papal nuncio was “trying to quieten things down”.