Cardinal Kevin Farrell, head of the Vatican's family and laity office, told the Associated Press he is livid he was kept in the dark because he would have done something about it.
He spoke as the US church hierarchy came under fire from ordinary American Catholics, outraged that McCarrick's misconduct with men was apparently an open secret in some US church circles.
Pope Francis accepted McCarrick's resignation as cardinal on Saturday and ordered him to live a lifetime of penance and prayer pending the outcome of a canonical trial.
In an open letter on Tuesday, a contributor to the conservative Catholic magazine First Things urged Catholics to withhold diocesan donations to the US church until an independent investigation determines which US bishops knew about McCarrick's misdeeds - a "nuclear option" aimed at making the laity's sense of betrayal heard and felt.
Some outrage has been directed at Cardinal Farrell, 71, who was consecrated as a bishop by McCarrick in 2001 and served as his vicar general in the archdiocese of Washington until McCarrick's 2006 retirement.
Some Catholic commentators have speculated the Cardinal must have at least heard rumours that Catholic laity, students and professors at Catholic University in Washington and even some journalists had heard.
Cardinal Farrell lived with McCarrick, 88, and other priests and bishops in a converted school building off Dupont Circle that serves as a residence for Washington clergy.
But he said he never heard any rumours about his boss' penchant for young men, or suspected anything, and was not McCarrick's roommate as some bloggers have claimed.
"That might be hard for somebody to believe, but if that's the only thing on your mind, well then you'll focus on that," he said.
"I was focused on running the archdiocese. What Cardinal McCarrick was doing here, there and everywhere and all over the world, didn't enter into my daily routine of running the archdiocese of Washington.
"At no time did anyone ever approach me and tell me. And I was approached by over 70 victims of abuse from all over the United States after 2002," Cardinal Farrell said of the time the US sex abuse scandal first erupted.
"Never once did I even suspect," he said. "Now, people can say 'Well you must be a right fool that you didn't notice.' I must be a right fool, but I don't think I am. And that's why I feel angry."
McCarrick was initially removed from public ministry on June 20 after US church officials determined that an accusation he fondled a teenage altar server in New York in the 1970s was "credible and substantiated".
Since then, another man identified only as James has come forward saying McCarrick first exposed himself to him when he was 11 and then engaged in a sexually abusive relationship with him for the next 20 years.
McCarrick has denied the initial accusation but has not responded to the second one.
At the time of McCarrick's June removal, the New Jersey archdioceses of Newark and Metuchen revealed they had received three complaints from adults alleging misconduct and harassment by McCarrick and had settled two of them.
It was apparently no secret that McCarrick invited seminarians to his New Jersey beach house and into his bed, suggesting that some in the US hierarchy knew of his abuse of power but turned a blind eye.
As head of the most politically powerful US archdiocese, McCarrick took a lead role in the US bishops' 2002 response to the sex abuse scandal.
He served as a spokesman when the bishops were summoned to the Vatican that spring and then helped craft the "zero tolerance" policy they adopted at a landmark congress in Dallas later that year.
That hypocrisy is what is driving the sense of betrayal among rank-and-file Catholics, and the anger they are directing at McCarrick's fellow bishops.
"Not only did they not produce what they promised, but we have a level of downright depravity that was right in their midst while they were making these promises," said Marjorie Murphy Campbell, a civil and canon lawyer in Park City, Utah, who has called for an independent investigation into the scandal.
On Monday, the Catholic University of America revoked the honorary degree it gave McCarrick in 2006, following in the footsteps of Fordham University in New York.
Cardinal Farrell said he only met McCarrick after McCarrick arrived in Washington, where he was appointed archbishop in November 2000.
He said he never expected to remain working in the Washington archdiocesan chancery because he wanted to get back to being a pastor at the Annunciation parish on Massachusetts Avenue.
The cardinal added he turned down McCarrick's request that he give up the parish three times, but then was told by the Vatican ambassador that he was being made a bishop.
He also said he did not know anything about misconduct with seminarians at a New Jersey beach house and that no accusations against McCarrick were ever brought to the Washington archdiocese, which from 2002 onwards was deluged with claims from victims of sexually abusive clergy.
"If there were a complaint... I would have discussed it with the (archdiocesan) chancellor, who was a woman at the time, a woman who was in charge of victims and in charge of all the telephone calls we would get," he said.
The current archbishop of Washington, Cardinal Donald Wuerl, has said a review of archdiocesan records showed no complaints about McCarrick.
"There is no record there," Cardinal Farrell told AP. "Because I would know about it."
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