NEW YORK — A group of young Catholics has urged the U.S. bishops to “take clear action” by conducting an independent investigation of who knew what and when about actions by Archbishop Theodore E. McCarrick, who has been accused of sexual abuse.

They also stressed that the bishops should engage in “formal acts of public penance and reparation” for what has happened.

“An Open Letter from Young Catholics” was published online Aug. 8 on the website of First Things, a journal of the Institute on Religion and Public Life, which is a research and education center based in New York. The journal is printed 10 times a year.

The letter, addressed to “Dear Fathers in Christ,” had 43 signatures. The group includes authors, writers and editors; the heads of Catholic and other organizations; and professors, assistant professors, doctoral candidates and research scholars in various disciplines at Catholic and secular universities in the U.S. and elsewhere.

“You are the shepherds of the Church. If you do not act, evil will go unchecked,” the letter said.

It asked the bishops to “agree to a thorough, independent investigation into claims of abuse by McCarrick, both of minors and of adults. We want to know who in the hierarchy knew about his (alleged) crimes, when they knew it and what they did in response. This is the least that would be expected of any secular organization; it should not be more than we can expect from the Church.”

The letter also asked that “the silence surrounding sexual impropriety in the Church be broken” and that the bishops “take clear action when priests flout the Church’s sexual teaching and that networks of sexually active priests be rooted out.”

It said good priests should have the freedom to tell their bishops what they know, without fear of reprisal.

The letter writers described themselves as some being younger than others but that they were “all children in the decades leading up to the sexual abuse crisis of 2002.”

They committed themselves to the following actions:

— “We will refuse to be silent when we see or hear of sexual assaults taking place anywhere in the Church and by any person, clerical or lay.”

— “When those we know are assaulted, we will encourage the victims to come forward. We will stand with them until justice is done.”

— “We will not accept silence and inaction. Rather, we will publicly name and expose those who harm others and superiors who fail to take action when others are harmed.”

They said they are “grateful for the way good priests and bishops lay down their lives for us day after day. They say the Mass, absolve us from sin, celebrate our weddings and baptize our children.”

The letter writers also said they would speak out when they “discover clerical sexual impropriety” and would work to “protect the good priests and seminarians who are threatened when they refuse to condone the sins of their fellow clerics, or when they speak out about them.”

The letter did not mask its anger or disappointment with the current situation in the Church.

“We are also angry,” the letter said, about the “credible and sustained” report of McCarrick’s abuse of a minor and over allegations of his abuse of seminarians and young priests. The group also is angry “that ‘everybody knew’ about these crimes, that so few people did anything about them and that those who spoke out were ignored.”

The letter mentioned “reports of networks of sexually active priests who promote each other and threaten those who do not join in their activities; of young priests and seminarians having their vocations endangered because they refused to have sex with their superiors or spoke out about sexual impropriety; and of drug-fueled orgies in Vatican apartments.”

The writers demanded: “Bishops to make clear that any act of sexual abuse or clerical unchastity degrades the priesthood and gravely harms the Church.”

They wrote that they are “scandalized” that McCarrick held a position of authority in the Church and said they are “alarmed by reports that Pope Francis acted on McCarrick’s guidance in creating cardinals and appointing men to senior positions in the Church,” adding that “men McCarrick mentored and lived with are now important archbishops and heads of Vatican dicasteries.

“We want to know what those men knew about McCarrick and when they knew it, especially since ‘everybody knew.’ If the pope himself knew, we want to know that as well,” the group added.