Catholic Church's "secret archives" detail playbook for concealing abuse

New details are emerging about how Catholic Church leaders protected priests accused of sexual abuse. A Pennsylvania grand jury says more than 300 priests abused more than 1,000 children, and likely thousands more, over seven decades.

A trove of documents containing allegations and admissions of sexual abuse were kept locked up in what the church calls its "secret archives," with the only key in the bishop's hands.

"The cover-up made it impossible to achieve justice for the victims," said Pennsylvania Attorney General Josh Shapiro.

He laid out a pattern of consistent, decadeslong cover-up across six dioceses.

The files contained a pattern of strategies that were practically a playbook for concealing the truth. Some of the tactics for church recordkeeping included euphemisms, like saying "inappropriate contact" or "boundary issues" instead of "rape."

Even if a priest was abusing children, they were allowed to keep their housing and living expenses. Above all, the church was told not to call the police and instead handle claims like a personnel matter.

As church officials protected predator priests, careers continued to rise.

"Bishop Wuerl is now Cardinal Wuerl," said Shapiro.

Washington, D.C., archbishop, Cardinal Donald Wuerl, presided over 32 accused priests during his 18 years at the Pittsburgh diocese. He sat down with CBS News the night before the report's release.

"During my tenure, we acted… very appropriately with many times removal from ministry, totally and completely," he said.

But according to the grand jury, in 1991, Wuerl reassigned an accused priest, Ernest Paone, to the Reno diocese. In 1995, he returned George Zirwas, a member of a pedophile community, according to the attorney general's office, to the ministry.

CBS News asked Wuerl about allegations that he and others were conspiring to cover up the abuse.

"I would have to say that's just totally false," he said.

CBS News reached out to Wuerl's representatives after the report's release, and they say he stands by his interview. So far, the Vatican has not commented. But there is a possibility clergy involved could face criminal charges if they failed to report certain abuse allegations.