The state of Missouri will investigate the Roman Catholic Archdiocese of St. Louis after it volunteered to open its files on allegations of sexual abuse by priests, the state's attorney general announced Thursday.

The Rev. Robert Carlson, the archbishop of St. Louis, volunteered the diocese's cooperation in a letter to Attorney General Josh Hawley on Thursday, a day after protesters in St. Louis demanded a grand jury investigation.

In his letter to Hawley, Carlson said he was "aware of the public's requests to your office."

Carlson said that the archdiocese's own investigation had found that protections for children are "appropriate and robust" and that he invited an "independent determination of our handling of allegations of clergy sexual abuse in the Archdiocese of St. Louis."

Carlson said at a news conference Thursday that the files address "anyone who has been accused of sexual abuse."

"We did this for the credibility of the archdiocese," he said.

Sandra Price, the diocese's executive director of child and youth protection, said 27 priests named in the files are still alive.

Hawley welcomed the invitation in a letter to Carlson and said in a conference call with reporters that he hoped the state's other dioceses would participate.

Cooperation from the dioceses is crucial because it's local prosecutors who have jurisdiction to issue subpoenas and to bring charges, not the state. But Hawley said the report can and will include recommendations for local charges if appropriate.

Representatives of the Diocese of Kansas City-St. Joseph and the Diocese of Jefferson City told The Associated Press that they would cooperate. A spokeswoman for the Diocese of Springfield-Cape Girardeau didn't immediately return a call seeking comment.

Hawley put no timetable on the investigation, but said he wanted to move quickly because "the statute of limitations is always, always a concern."

A Pennsylvania grand jury investigation last week alleged abuse of more than 1,000 children by 301 "predator priests" in six dioceses over 60 years. But only two indictments have been filed because the statute of limitations has expired in nearly all of the reported cases.

The statute of limitations in Missouri gives childhood sexual abuse accusers until age 28 or until three years after the discovery of physical or psychological injury from the abuse to file suit.

"It's important to me, because I am a mother of a victim who was abused," Mary-Ellen Kruger told NBC affiliate KSDK on Wednesday as she protested outside the attorney general's office in St. Louis.

Kruger said her 15-year-old son was molested at a Catholic high school in 1985 and eventually died by suicide.

"For us to protect our children, we need to know who they are and where they are," she said of abusive priests.