The terms of reference for the Charleton Tribunal were agreed by the Irish government on Thursday.
It followed claims by Sgt Maurice McCabe that the Republic's penalty points system was fraudulent.
County Donegal based garda Keith Harrison said he hoped the inquiry would "establish the truth".
Sgt McCabe was investigated by the Republic's child and family agency (Tusla) following allegations of abuse, that were later found to be untrue.
Mr Harrison claims he was also the subject of untrue abuse accusations.
"After a long and difficult battle to have all my complaints investigated, I would like to acknowledge the publication today of the expanded terms of reference of the Tribunal of Inquiry that finally includes an investigation of the ill-treatment of my family and I.
"The inclusion of an investigation of the ill-treatment of other whistleblowers within An Garda Síochána (Irish police) is a welcome development.
"I trust the inquiry will establish the truth and bring about a change within senior management of An Garda Síochána," he said.
The tribunal will prioritise allegations against Sgt McCabe, with other high-profile whistleblowers such as Mr Harrison included in a separate module.
It is expected to issue an interim report within three months.
An Irish policeman has welcomed his inclusion in the investigation of false allegations against garda whistleblowers.