Ireland's Catholic Church-established watchdog on child sexual abuse is to ask the Government to give it statutory powers to allow it share information among church authorities concerning allegations against priests, religious and church workers.

Head of the watchdog Teresa Devlin announced the move at a public hearing of a Royal Commission in Australia which is reviewing institutional responses to child sexual abuse there.

She said it would involve her board using legislation adopted by the EU to assess whether sharing sensitive information about alleged abusers is more important than protecting a suspect's privacy.

Giving testimony to the Royal Commission in Sydney earlier today, Ms Devlin - who is the chief Executive of the National Board for Safeguarding Children in the Catholic Church in Ireland - said some religious authorities in Ireland have concerns about sharing confidential information with her board because it is a non-statutory body.

The difficulties have surfaced publicly during the eight years of the board's existence, but Ms Devlin said they are now affecting its efforts to persuade the 190 church bodies - including dioceses and orders - to agree a new memorandum of understanding with it based on revised standards of child protection which it produced in 2015.

Ms Devlin said that her board is about to engage with Minister for Children Katherine Zappone to discuss the prospect of the Government conferring on it statutory powers to allow it regulate the controversial exchanges of data.

She traced the problem to the board's experience of priests who have been barred from ministry abroad travelling here to minister as priests.

She confessed that although the board has some ability to act as a "gate-keeper" through vetting and through monitoring church regulations for visiting priests, this was not always the case.

"So if I'm a priest and I'm going home on my holidays and I know who the parish priest is and he doesn't ask me for my celebret, my letter of good standing, and I'm out of ministry, nobody knows, so I could minister," Ms Devlin told the commission.

She said the board was learning "by default that people are moving around".

She explained that under current data protection laws, Catholic bishops and provincials of religious orders in Ireland cannot share the information with each other because they are separate legal entities.

"The only legal way in which that information can be shared is through the State authorities, through the police and social services," she continued.

"The police cannot share the information, and social services don't always share the information. So the only body that can systematically do that would be ourselves," Ms Devlin told the commission.

She said the NBSCCCI is trying to find ways in which it can legally receive and share the information.

She added that the easiest way is by getting the consent of the person who has given cause for concern, for the information to be shared with the NBSCCCI.

However, she warned that the person - also known as the "data subject" or respondent - may or may not give that consent.

Ms Devlin described the European Union's data protection laws as "very tight", requiring what is called a privacy impact assessment to establish the impact on an individual's privacy of sharing information about him or her.

She said the process involved the data holder establishing that "the rights of the child to protection are greater" than the right of the accused individual to privacy.

"But it's very complex," Ms Devlin continued. "So we're going to go and see the minister (for Children) in the hope that she will give us some regulation."

She explained that the statutory role the NBSCCCI is proposing would be to monitor the privacy impact assessment process and to report on it in its annual report.