(Abuse victim Joe Iacono looks on during a news conference where thousands of documents on victims of sexual abuse by Roman Catholic clergy from the Chicago Archdiocese were released in Chicago, Illinois, January 21, 2014. REUTERS/Jim Young)

Lawyers for victims of sexual abuse by Roman Catholic clergy on Tuesday released thousands of related documents from the Chicago Archdiocese, the latest in a series of such disclosures in the Midwest.

The documents concern 30 former Chicago-area priests accused of abusing minors during the last half century, according to the Archdiocese, one of the largest in the United States with 2.2 million Catholics.

The release, expected to reveal how the church responded to the allegations, is part of a mediation agreement between the Archdiocese and lawyers.

Ninety-five percent of the cases occurred prior to 1988, according to Chicago church officials. All of the priests involved in the document release are out of ministry, and 14 are deceased.