On Friday January 9, 1973, Cardinal William Conway, Primate of All Ireland and Archbishop of Armagh, unexpectedly cancelled a trip to Australia because of his "anxiety" over the Troubles in Northern Ireland.

The towering pipe-smoking prelate, know as 'Big Bill' on account of his brisk management style often bordering on bullying, confided to one observer that he had decided not to attend a Eucharistic Congress in Melbourne "in view of the political situation in Northern Ireland".

This decision was puzzling, because Pope Paul VI, to whom Cardinal Conway enjoyed regular access with updates on developments in Northern Ireland, was heading to Melbourne.

It was strange that Cardinal Conway had not opted to travel to Melbourne to unburden his "anxiety" to the Pontiff.

The answer is now known, with the Northern Ireland Police Ombudsman's report finding that the RUC, Catholic Church and British government colluded to protect Derry priest Fr James Chesney due to his suspected involvement in the 1972 Claudy bombing.

In December 1972, Cardinal Conway made a note in his diary about engaging in "a rather disturbing tete-a-tete . . . about C", referring to a meeting with William Whitelaw, Northern Ireland Secretary of State. Cardinal Conway acknowledged that Chesney, his former pupil, was "a very bad man", according to an RUC record of the row.

Mindful of the commandment, 'thou shalt not kill', the canon law process for defrocking the Derry priest should have been initiated.

Instead, Cardinal Conway colluded in a church-state conspiracy by pledging to "see what could be done".

The row centred on the cardinal's preference to transfer the errant cleric to Donegal, as against the RUC chief constable's wish that he be transferred to Tipperary. This was a compromising position for Cardinal Conway, knowledge of which would have embarrassed Pope Paul VI.

It was not until 1973 that Chesney was sent to Donegal, to the Raphoe diocese under 'Big Bill's' friend, Bishop Anthony McFeely.

This was Cardinal Conway's dark secret when he died in 1977.

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