Ed Mulhall's decision to retire as the managing director of RTE news and current affairs was a direct response to the "political decision" by Communications Minister Pat Rabbitte to refer the libelling of Fr Kevin Reynolds to the Broadcasting Authority of Ireland (BAI).
Mr Mulhall is understood to believe that while he was not directly responsible for the worst libel in RTE history, he had a duty as the top man to "carry the can" for the Primetime Investigates fiasco.
Mr Mulhall declined to speak to the Sunday Independent when visited at his home last week -- but sources close to him said Mr Rabbitte's decision to refer the Mission to Prey programme to the BAI meant the affair took on a different dimension.
"There are still processes ongoing and I am not saying anything right now," he said.
Mr Mulhall was initially very "upset" by comments made by RTE chairman Tom Savage to the Sunday Independent which inferred the fault lay with him and not director general Noel Curran, it has emerged.
Mr Mulhall is said to have been shocked that Mr Savage spoke publicly before three separate inquires had concluded, but he has since "moved on".
Many RTE staff think Mr Savage "shafted" Mr Mulhall -- a popular figure in Montrose.
However, according to a number of people close to Mr Mulhall, the most difficult adjustment during the entire process was not the decision to take early retirement, but rather the initial choice to step aside while investigations were ongoing.
"It was the political decision to refer the matter to the BAI that was a game changer for Ed. It was not a case of the BAI doing its own thing, Mr Rabbitte's decision made everything different," an RTE source said.
"It changed the dynamic because he was head of news and head of current affairs."
Mr Mulhall is set to receive a retirement package in excess of €300,000, according to media reports, but Mr Curran insisted there had been no special arrangement to facilitate his departure.
"In the case of Ed Mulhall it is a completely personal decision and there is a package currently available to staff and Ed is going under that package," Mr Curran said.
"There is no special arrangement or deal. In terms of other people, and I do need to be careful, we do have an independent investigation board which is looking into personnel matters around this," he added.
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Mr Mulhall's supporters in RTE believe it was unfair for him to carry the can as he was in the middle of overseeing the visits of Queen Elizabeth and US President Barack Obama when asked for his approval for the broadcast.
In a note to all RTE staff sent before his departure was announced, Mr Mulhall said the decision not to return to his job was very "difficult".
"To all, I have decided not to resume my role as MD news and current affairs and also that I have retired from the organisation.
"These were difficult decisions not least because of the support I have received from staff since I offered to step aside in November following the government decision to refer the Mission to Prey programme to the BAI," he said.
"It is, however, my considered view that it is in the best interests of RTE news and current affairs that it faces the challenges ahead under new leadership," he added.
Mr Mulhall's final duty for RTE was to contribute to the "best of my ability" to the production of new journalism guidelines for RTE editorial staff.
"I am very proud of the work we have done together," he said.
Yesterday, it emerged that the BAI had recommended RTE pay a fine of €200,000 for "breaches in fairness" procedures during the making of Mission to Prey.