A priest set to be elevated to an auxiliary bishop by Cardinal Blase Cupich was investigated a decade ago over an allegation of sexual misconduct with a child that state authorities deemed “unfounded,” the Archdiocese of Chicago revealed on Friday.

The archdiocese made the unusual disclosure about Rev. Robert Casey Friday evening “for the sake of transparency” ahead of Monday’s Ordination Mass at Holy Name Cathedral, where he and two other priests will become Cupich’s auxiliary bishops, according to archdiocese spokeswoman Anne Maselli.

Casey, 50, was removed from the ministry for about four weeks in 2008 as the Illinois Department of Children and Family Services investigated a complaint about an incident alleged to have occurred that year, Maselli said. State investigators determined the claim was “unfounded,” the archdiocese said.

“According to a letter from DCFS communicating this decision, ‘this means that credible evidence does not exist to support the allegation made,’ ” the archdiocese said in their Friday statement. “Given this determination, Bishop-elect Casey was returned to ministry.”

Neither Casey nor a DCFS spokesman could be reached for comment Friday night.

Casey was the pastor of Our Lady of Tepeyac Parish in the Little Village at the time the complaint surfaced, according to a church biography. The next year, he moved to become pastor of St. Barbara Parish in Brookfield and again in 2016 to St. Bede the Venerable Parish on the Southwest Side. That’s where he has served up to the July 3 announcement that he had been appointed an auxiliary bishop by Pope Francis.

Casey also serves on the archdiocese’s Placement Board, assisting with the assignment process of priests to parishes.

The announcement came a night before Cupich is scheduled to celebrate a special Mass Saturday night at Holy Name in response to the Catholic Church’s ongoing clergy sexual abuse crisis. The cardinal has caught flak over the last two weeks for saying the Church has “a bigger agenda than to be distracted by all of this” — comments deemed “tone-deaf” by seminarians struggling with the scandal.

The archdiocese on Friday noted that Rev. Mark Bartosic and Rev. Ronald Hicks, who will also be ordained auxiliary bishops on Monday, were also “vetted in accordance with regular procedure” and “[n]one has a substantiated allegation of sexual misconduct.”

“The bishops-elect were seminary classmates and share a fluency and interest in Hispanic language and culture so vital in serving our parishioners,” Cupich said in a July statement announcing the new auxiliary bishops. “Each of them has distinguished himself through dedication, service and a life-long witness to the Gospel. We welcome their ideas and energy as we renew the Church.”

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