Allegations of bullying, harassment and isolation of a whistleblower in the Irish Prison Service have been upheld in a review authored by a retired judge, seen by RTÉ's This Week.

Judge William Early's report, which was completed last February, found the prison officer had been "penalised" and "isolated" by the prison service after he made a protected disclosure about the use of resources within one of the country's prisons.

The review found he was denied career opportunities and exposed to considerable stress as a result of raising his concerns.

Examples given by the officer of isolation and harassment by prison authorities included an incident of serious assault in the prison in March 2015 in which he witnessed colleagues being slashed with a blade and another sustaining a broken ankle.

His claim that he was not interviewed about the incident due to being isolated by prison authorities at the time was not denied or refuted by the IPS.

A prosecution could not be mounted, according to the Director of Public Prosecutions, due to a lack of evidence.

Judge Early's review found "the incident of March 2015 suggests a serious criminal offence was committed... it is quite extraordinary that a primary witness to a serious assault was not interviewed".

In another incident in February 2015, the prison officer was notified by local gardaí that they were investigating a report by a member of the public that he and his wife had been filmed in suspicious circumstances at a local shopping centre.

The prison officer alerted the prison authorities of the incident.

He told them that he would be taking security precautions and that the incident was a source of considerable stress to him and his wife.

He was not made aware until August 2016 that the investigation into the filming incident had been concluded over a year earlier and had found he was not at risk.

However, the prison authorities were made aware of the conclusion of the investigation 14 months earlier in April 2015. Judge Early's review found that the stress of believing the risk was ongoing, which exacerbated an existing medical condition and caused considerable anxiety to the officer's wife, "could have been prevented or alleviated by a timely transmission of the [Garda] Report to the Discloser by the IPS".

"It is difficult to understand how information of such importance to the Discloser was not given to the Discloser in a timely manner."

The officer's wife suffered a stress-related stroke in 2015.

The findings of Judge Early's report overturn those of an earlier report by the Department of Justice's Internal Audit Unit, which had not upheld the officer's allegations.

Judge Early's review described the IAU report as "inadequate" and that its conclusions were "not in conformity with the preponderance of the evidence".

The judge was appointed as external reviewer to the officer's complaint on foot of his appeal of the IAU report.

The prison officer, who was described as having acted in good faith, has received apologies from both the Department of Justice and the Irish Prison Service for the handling of his case.

His complaints were described in Judge Early's review as being "detailed, lucid and cogent".

A prison governor quoted in the Early Review described him as "very respectful and has never been of any trouble in the prison service".

The officer has also raised concerns about the inadequacies of the IPS's protected disclosure management and his treatment with the Oireachtas Public Accounts Committee.

These include concerns that no disciplinary action has been taken on foot of Judge Early's review.

In a written statement, the IPS told RTÉ: "The IPS is not in a position to discuss individual protected disclosures that may have been made or the identity of any persons making such disclosures. 

"In general terms, the IPS is determined to ensure that it has robust procedures in place to govern the making of protected disclosures and how disclosers are treated. 

"The IPS is currently considering what steps we can take to further enhance our arrangements, including in the context of all the guidance and recommendations that are available to us."

Call for dedicated whistleblower manager

Fianna Fáil TD for Kilkenny and former Public Accounts Committee chairman John McGuinness has supported the whistleblower's call for an independent protected disclosure manager for the Prison Service.

Mr McGuinness has also called for action to be taken on foot of Judge Early's report.

Speaking on This Week, he said: "Concrete action needs to be taken in relation to this disclosure because of the fact that it's being made by an individual at the coal face of the Prison Service where you're dealing with those who have been put into custody by the Court Services.  

"It's my firm belief that those who are involved in bullying or who in some way have been found to be involved in wrongdoing against another employee to cause such a devastating effect as it has had on this family, they should be sanctioned in some way. Otherwise the culture will just continue to prevail."