The taxpayer is to cover Sean Guerin's legal costs in the action being taken against him by Alan Shatter.
It has emerged the Government will indemnify Sean Guerin in the High Court case and will cover any of his legal fees in defending the case.
Mr Guerin was hired by the Government to report into its handling of Maurice McCabe's allegations of Garda malpractice.
His report found major shortcomings with the response of the Department of Justice, and its then-minister Alan Shatter who resigned as a result.
Last week Deputy Shatter launched a High Court bid to overturn some of the findings, saying Mr Guerin should have interviewed him, and that he was denied his rights to fair procedure.
However, now it has emerged that the Government will indemnify Mr Guerin by covering any of the costs he will face in the legal action.
Enda Kenny's department is to offer Mr Guerin the same legal cover as a civil servant, meaning it will pay Mr Guerin's legal bills in his defence against one of Enda Kenny's former allies.