There is no evidence child protection workers acted with "malice of intent" in the Garda whistleblower scandal, the head of the state child agency has said.
Tusla is among those being investigated over its role in an alleged smear campaign against Sergeant Maurice McCabe, in a controversy that has brought the government close to collapse.
The agency had a file containing false allegations of sexual abuse against Mr McCabe, at a time when he was exposing wrongdoing within the force.
Fred McBride, chief executive of Tusla, confirmed it began "formally engaging" with the public tribunal set up to probe the affair on Tuesday.
Before a parliamentary committee, he said he was restrained on how much he could say about matters under investigation by the inquiry, headed by Supreme Court judge Peter Charleton.
"But I think it is important to point out that I have no knowledge or evidence that Tusla staff acted with any malice of intent," he said.
"I also wish to make it clear that if I did receive - or in any time in the future receive - such evidence or information, I will intervene personally and immediately and publicly."
Mr McBride added that "mistakes were made" and that the agency was looking forward to addressing the affair "in its totality" during the public inquiry.
"Indeed, as far as I'm concerned the inquiry can't come soon enough, in order that all the facts are known and responsibility and accountability can be properly and fairly attributed," he said.
Mr McBride told the Joint Committee on Children and Youth Affairs that dealing with historical abuse allegations was particularly challenging for the agency.
This is when an adult comes forward to disclose abuse as a child.
"It is especially challenging because the legal framework around this is not specific enough," he said, adding that the agency needed more expertise and skills in the area.
Sgt McCabe was at the centre of an unfounded and false report on a Tusla file of an allegation of sex abuse against a colleague's daughter.
A counsellor working on behalf of the agency had claimed the error was made when details from a different case were cut and pasted on to a file.
Mr McBride said he wanted to reiterate an apology "to people affected by our mistakes and for the distress and upset they have endured".
He added: "I accept that public confidence in the system may well have been undermined because of that.
"But what has happened here is not reflective, I think, of the high standards that staff hold themselves to, or that I as chief executive hold them to - particularly in relation to the handling of sensitive information."