The Vatican and cardinals attending the session said the O'Brien case didn't come up during formal or informal conversations.
"It's a tragic moment for him," George said.
At a briefing discussing the priorities for the future pontificate, George said the next pope will have to follow canon law and keep priests who molested children out of parishes.
"He obviously has to accept the universal code of the church which is zero tolerance for anyone who has ever abused a minor child and therefore may not remain in public ministry in the church," George said. "That has to be accepted. I don't think that will be a problem."
Separately, the Vatican is still reeling from the fallout of the scandal over leaked papal documents, and the investigation by three cardinals into who was behind it.
American cardinals seem particularly keen to get to the bottom of the Vatican dysfunction, and they have had access to a very knowledgeable tutor, Archbishop Carlo Maria Vigano, the Vatican's ambassador to Washington.
Vigano's letters to the pope were the most explosive leaks of documents last year; in them, Vigano pleaded with Benedict not to be transferred after exposing alleged corruption in the awarding of Vatican contracts that cost the Holy See millions of euros (dollars).
Vigano was named the Vatican's ambassador to Washington, and as such has been able to give U.S. cardinals a clear-eyed view of the true state of the Vatican, said Corriere della Sera commentator Massimo Franco.
"They have appreciated him very much because he doesn't read the Vatican situation with a rosy lens, a rosy view," Franco said in an interview.
In his new book "The Crisis of the Vatican Empire," Franco paints a portrait of a Vatican completely falling apart, with financial scandals at its bank, backstabbing among its ruling class and the sex abuse scandal discrediting the church on the global stage.
"If we think of the pope, in a way the pope decided to sacrifice himself because he couldn't change anything," Franco said.
Coupled with the upheaval of Benedict's resignation, the scandals have contributed to create one of the most unclear papal elections in recent times.
"It will be a very open conclave with a very unpredictable outcome," Franco said.
In one of his last audiences before resigning, Benedict gave the three cardinals who investigated the leaks the go-ahead to answer their colleagues' questions about the results of their investigation.
"There are members of the College of Cardinals who are interested in having information that has to do with the situation in the Curia and the church in general and will ask to be informed by their colleagues," the Vatican spokesman the Rev. Federico Lombardi said.
Trisha Thomas and Rachel Zoll contributed to this report.
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