Six Aussie prison officers who were threatened with the sack after they blew the whistle on their bosses on Facebook will have their cases reinvestigated.

The Department of Corrective Services told the officers in April it was sacking them for misconduct after they posted disparaging comments about Corrective Services Commissioner Ron Woodham and Deputy Commissioner Gerry Shipp. The six created a group which was entitled "Suggestions to help big RON save a few clams" and offered ways for the department to save money without privatisation.

The Public Service Association applied to the Industrial Relations Commission for an unfair dismissal case to be heard before the officers were fired. Justice Frank Marks said that he had some concerns about the fairness of the investigations into the officers.

The PSA said that the Facebook Six had been investigated and fired by Woodham and Shipp and were clearly biased. Corrective Services has now agreed to appoint a third party to look into the case but has not specified whether it will be an entirely new investigation or based on existing documents and statements.