[Editor's Note: This story was updated at 4:10 p.m., central.]
The archbishop of St. Paul-Minneapolis has voluntarily removed himself from public ministry while local authorities investigate an accusation against him of inappropriate touching four years ago.
The Twin Cities archdiocese learned last week of an allegation that Archbishop John Nienstedt touched a young man's buttocks in 2009 during a group photo session following an area confirmation ceremony. The archdiocese said it directed the mandated reporter who first learned of the alleged incident to report it to St. Paul police.
Upon consulting with Carlo Maria Viganò, the apostolic nuncio to the United States, Nienstedt decided to step down from public ministry effective immediately while the investigation is ongoing, according to the archdiocese. Auxiliary Bishop Lee Piché, the vicar general, will take the archbishop's place in public duties.
Spokesman Jim Accurso said the archdiocese could not comment further as the investigation is pending.
Addressing the incident in what he described as a "difficult letter for me to write to you," Nienstedt denied any wrongdoing.
"I do not know the individual involved; he has not been made known to me. I presume he is sincere in believing what he claims, but I must say that this allegation is absolutely and entirely false," he wrote.
"I have never once engaged in any inappropriate contact with a minor and I have tried to the very best of my ability to serve this Archdiocese and the church faithfully, with honor and due regard for the rights of all, even those with whom I disagree," he wrote in the letter .
Nienstedt explained in the letter his typical procedure for photo shoots like the one in question, saying he normally stands with one hand on his crozier, or staff, and the other on the right shoulder of the newly confirmed or on his pallium.
"I do that deliberately and there are hundreds of photographs to verify that fact," he wrote.
While the investigation plays out, Nienstedt said he will use the time to pray for Twin Cities Catholics and the accuser and asked for Catholics to pray for him.
"True, I am a sinner, but my sins do not include any kind of abuse of minors," he said. "I have met victims and I know the lasting damage that such abuse causes."
The archdiocese called the steps it has taken, including Nienstedt's removal from public ministry, as moves that "further confirm that all within the archdiocese will be subject to the internal policies we have established."
Nearly two weeks ago, the archdiocese released the names of 30 former priests with substantiated claims of child sex abuse. As part of the disclosure Nienstedt reiterated the archdiocese's policy as it pertains to abuse allegations.
"It is the practice of the archdiocese to report promptly to law enforcement all allegations of clergy sexual abuse of minors. Any clergy member facing a credible claim of sexual abuse of minors will be removed from ministry pending an investigation of the claim," he wrote in a Dec. 5 column  in the Catholic Spirit, the archdiocesan newspaper. An amendment to that policy now requires the archdiocese to post credible and substantiated claims on its website in an "Advocacy and Victim Assistance" section.
That Nienstedt applied the same standards to himself that apply to priests was a welcome move, said Fr. Jim Connell, a Milwaukee archdiocesan priest and member of the abuse victims' advocacy group Catholic Whistleblowers.
"It's the right thing to do. It's the right thing to do to step out of ministry, and it's what we ask the priests to do. I'm glad to see the archbishop did the same thing," Connell told NCR.
In the recent past, bishops accused of sexual impropriety have not necessarily stepped aside as investigations were underway.
Some bishops -- including Thomas Dupre of Springfield, Mass., Joseph Symons and Anthony O'Connell of Palm Beach, Fla., and J. Kendrick Williams of Lexington, Ky. -- resigned only after accusations of sexually abusing minors were deemed credible. Accusations against Dupre, Symons and O'Connell dated back to their time as priests.
In May 2002 retired Sioux Falls, S.D., Bishop Paul Dudley voluntarily withdrew from public ministry in the Twin Cities archdiocese, where he resided, when accusations emerged that he had fondled an altar boy on multiple occasions while a priest in Minneapolis. A church review found no evidence to support the claims.
Two prelates, Archbishop Robert Sanchez of Santa Fe, N.M., and Bishop G. Patrick Ziemann of Santa Rosa, Calif., each resigned when accused of having sexual relations with adults while bishops, in 1993 and 1999, respectively.
The U.S. bishops' pact for addressing clergy sex abuse, the Charter for the Protection of Children and Young People , provides parameters for bishops in handling alleged abuse by a priest or deacon, but offers little guidance when a bishop himself is accused.
"There's not a process whereby the pope would suspend him the way a bishop suspends a priest or puts him on administrative leave," said Michael Merz, an Ohio federal district court judge and former chair of the U.S. bishops' National Review Board.
At the end of the charter in a statement on episcopal commitment, it briefly addresses what to do when a bishop is accused.
"If a bishop is accused of the sexual abuse of a minor, the accused bishop is obliged to inform the Apostolic Nuncio," it states, also requiring a fellow bishop to alert the nuncio should he learn of an allegation of abuse by a bishop. The nuncio is also to be informed in cases of financial demands in a settlement related to sexual misconduct allegations of a bishop.
[Brian Roewe is an NCR staff writer. His email address is email@example.com. Follow him on Twitter: @BrianRoewe .]