A Wisconsin bishop has joined the president of the U.S. Bishops Conference in calling for an investigation into “credible allegations” of grave misconduct by a series of high-ranking Catholic prelates, including Pope Francis, in dealing with sex abuse.

Madison Bishop Robert C. Morlino issued a public statement Monday asserting that recent accusations by Archbishop Carlo Maria Viganò, the former papal nuncio to the United States, merit to be considered credible allegations and therefore must be investigated.

Archbishop Viganò “has offered a number of concrete, real allegations in his recent document, giving names, dates, places, and the location of supporting documentation – either at the Secretariat of State or at the Apostolic Nunciature,” Bishop Morlino states. “Thus, the criteria for credible allegations are more than fulfilled, and an investigation, according to proper canonical procedures, is certainly in order.”

In a written 11-page “testimony” published Saturday, Archbishop Viganò said that Pope Francis had reinstating Cardinal Theodore McCarrick to a position of prominence despite direct knowledge of McCarrick’s sexual abuse against seminarians and priests.

The archbishop alleged that Pope Benedict XVI had imposed “canonical sanctions” on Cardinal McCarrick in 2009-2010 forbidding him from traveling, celebrating Mass in public, or participating in public meetings, but that Pope Francis later lifted these sanctions and made McCarrick a close personal advisor with a hand in the naming of future bishops.

Now that “the corruption has reached the very top of the Church’s hierarchy,” Viganò wrote, “my conscience dictates that I reveal those truths regarding the heart-breaking case of the Archbishop Emeritus of Washington, D.C., Theodore McCarrick, which I came to know in the course of [my] duties.”

In his statement Monday, Bishop Morlino reiterated the thoughts of Cardinal Daniel N. DiNardo that Archbishop Viganó’s recent report “brings particular focus and urgency” to the examination by the USCCB of the grave moral failings of bishops. The questions raised “deserve answers that are conclusive and based on evidence. Without those answers, innocent men may be tainted by false accusations and the guilty may be left to repeat the sins of the past,” he said, citing DiNardo.

Bishop Morlino also expressed his “disappointment” in Pope Francis for refusing to confirm or deny the Viganò allegations on the return flight from Dublin to Rome this weekend, choosing instead the strategy of “no comment.”

While Pope Francis expressly said that such a judgment of the allegations should be left to the “professional maturity” of journalists, Morlino said that in the United States and elsewhere, “very little is more questionable than the professional maturity of journalists.”

“The bias in the mainstream media could not be clearer and is recognized almost universally,” Morlino said. “I would never ascribe professional maturity to the journalism of the National Catholic Reporter, for example. (And, predictably, they are leading the charge in a campaign of vilification against Archbishop Viganò.)”

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