Father Hans Zollner, one of the leading members of the Vatican committee against child sexual abuse, said on Wednesday he had resigned from the group, citing concerns over the way it was operating.
Zollner was one of the founding members of the Pontifical Commission for the Protection of Minors, which Pope Francis established in 2014 as part of efforts against the decades-old scandal of paedophilia within the Roman Catholic Church.
His abrupt departure represents a sharp blow to its image and comes after several members resigned early on, complaining the commission had no real power and met with internal resistance.
"Over the last years, I have grown increasingly concerned with how the commission, in my perception, has gone about achieving (the goal of protecting children and vulnerable persons)", the Jesuit priest said in a statement.
Zollner said his resignation was effective March 14. He added that he could not live with problems "particularly in the areas of responsibility, compliance, accountability and transparency".
The commission's head, U.S. Cardinal Sean O'Malley, said earlier on Wednesday that Zollner had stepped down because of a heavy workload.
Last year, the pope gave the commission greater clout when a new Holy See constitution placed it inside the Vatican's doctrinal department, which rules on abuse cases, and mandated it to produce an annual report on clerical sex abuse.
In his statement, Zollner denounced unclear hiring practices, roles and the commission's undefined relationship with the Vatican's doctrine office.
He also complained about "inadequate" financial and decision-making accountability.
Zollner, who also leads a centre for the study of abuse at Rome's Pontifical Gregorian University, said he remained open to talks with the commission and hopeful it could resolve its issues.
He publicised his resignation days after Francis updated rules on dealing with sexual abuse in the Catholic Church, expanding their scope to include lay Catholic leaders and spelling out that both minors and adults can be victims.
Abuse scandals have shredded the Vatican's reputation and have been a major challenge for the pope, who has passed a series of measures over the past 10 years aimed at holding the Church hierarchy more accountable, with mixed results.
(Reporting by Alvise Armellini, editing by Crispian Balmer and Josie Kao)
