PHOENIX (CNS) — The Diocese of Phoenix said retired Bishop Thomas J. O’Brien, who headed the diocese from 1982 to 2003, “categorically denies” an allegation that he sexually abused a young boy while the youngster was in grade school in the late 1970s and early 1980s.

A civil lawsuit has been filed against the diocese, several parishes and Bishop O’Brien, now 81.

According to its records, the diocese said in an Aug. 3 statement, Bishop O’Brien “was never assigned to any of the parishes or schools identified in the lawsuit, and no specific information has been presented which connects Bishop O’Brien to the plaintiff.”

The diocese said it immediately contacted the Maricopa County Attorney’s Office “upon learning of these allegations in September of 2016, and has offered its assistance and cooperation with any law enforcement investigation into the matter.”

“Because this is a pending litigation matter, we will not be sharing additional information,” it added.

The lawyer for the unnamed plaintiff told The Associated Press that his client had not remembered the alleged abuse until he began making plans for his son’s baptism. He began having flashbacks about it, said attorney Tim Hale. His client is now 47 and lives in the Tucson area.

Bishop O’Brien, a native of Indianapolis, was ordained a priest for the Diocese of Tucson in 1961 and then was assigned an associate pastor at Immaculate Conception Church in Douglas. Three years later he was named associate pastor for two parishes in territory that would become part of the Diocese of Phoenix when it was established in 1969.

He served as vicar general and in late 1981 was named bishop of Phoenix by St. John Paul II. He was installed in January 1982.

In 2003, in an agreement to avoid criminal prosecution, Bishop O’Brien gave up some of his diocesan administrative duties and apologized for allowing priests he knew were suspected of sexual abuse to continue working with minors.

The agreement was signed by the bishop and Maricopa County Attorney Richard M. Romley May 3, 2003, and announced in early June of that year. It required the bishop to delegate to a “moderator of the curia” certain administrative duties, including responsibility for revising and enforcing diocesan sex abuse policies. At the time, Romley also announced that six priests were being indicted in child sex abuse cases after a yearlong investigation.

Later in June 2003, Bishop O’Brien announced the Vatican had accepted his resignation. He said in a statement he made the decision to resign with “a heavy heart and great sorrow.”

A day before his resignation was accepted, he was formally charged with a felony of leaving the scene of an accident in which a pedestrian, Jim L. Reed, 43, was killed. He was convicted and sentenced to 1,000 hours of community service.

In its Aug. 3 statement about the lawsuit, the Diocese of Phoenix reiterated its commitment “to protecting all young people” and said it will “continue to work diligently to keep our young people safe.”

“We are dedicated to providing a safe environment in which every individual is valued and honored as created in the image and likeness of God,” it said. “Anyone who has been a victim of abuse or who may have information concerning these crimes is encouraged to call a local law enforcement agency.”

It added, “We continue to pray for all those who have been harmed by childhood abuse and will remain vigilant to protect the dignity of every person.”