From "The End of One Mystery," Inside the Vatican, by the editor (July 19, 2009):
Conversation between Robert Moynihan (editor of Inside the Vatican) and an unnamed Vatican official:
"Some are thoughtless. Some are persuaded the Church should be changed. Some just flow with the tide. Some are motivated by money. And then there are those who serve other masters. That was the case with Bugnini..."
I was startled. Not because of what he said, because it is an old allegation, but because of the way he said it, as if it was something settled, beyond discussion.
"Of course, I have heard that," I said, "but why do you say it so bluntly, as if it were certain? I thought it was just an allegation?"
"It is certain," he said. "At least, as certain as anything can be in this world. He went to a meeting in the Secretariat of State, with his briefcase. It was in 1975. Later that evening, when everyone had gone home, a monsignor found the briefcase Bugnini had left behind. The monsignor decided to open it to see who the owner was. And when he opened it, he found letters inside addressed to Bugnini, as to a brother, from the Grand Master of Italian Freemasonry..."
"But could those letters have been forgeries?" I asked. "Could someone have opened the briefcase, seen it was Bugnini's, and then slipped these false documents inside, to frame him?"
"Well, theoretically, I suppose, that is possible. [Note to readers: Bugnini himself always said the allegations were false, that he was never a freemason, and that the charges were made against him by disgruntled conservatives who opposed the work he had done on the liturgy.] But Paul VI, at least, didn't think so. When the evidence was brought to him, he came to the conclusion that Bugnini needed to be removed immediately from his post. Bugnini was made the papal nuncio in Iran. After more than 25 years as the head of the liturgical reform, he was abruptly fired and sent to a country where there are hardly any Catholics at all. It was a type of banishment.
Cf. "Was Bugnini a Mason?" in Tradition in Action.