Allegations have been made by senior gardaí of a deliberate campaign by Garda management to undermine the professional and personal reputations of Garda whistleblowers. Senior gardaí have given details of the alleged campaign to the Minister for Justice under the Protected Disclosures Act. So who are the Garda whistleblowers and what happened?
In 2008, the Westmeath-based sergeant raised concerns with his superiors about senior gardaí quashing penalty points. Nothing was done but in December 2012, he was banned from using Pulse, the Garda's communication and data storage computer system through which he had been able to analyse the penalty points system and identify questionable quashing of offences.
Controversy over the treatment of Sgt McCabe and a swirl of claims and counter-claims about investigations into his claims led to the resignations of then Garda commissioner Martin Callanan and minister for justice, Alan Shatter.
In due course, Sgt McCabe was vindicated in relation to his central complaint.
JOHN WILSON Penalty points were also at the heart of the case of former garda John Wilson's whistleblowing which ran in parallel with Sgt McCabe's efforts to draw attention to abuses of the system. Mr Wilson told TDs about malpractices in the application of penalty points after failing, in his view, to get the matter dealt with adequately through the Garda's internal complaints system. He retired in 2013 and brought, but lost, a High Court challenge to Garda findings that he had breached discipline by his actions.
NICK KEOGH In May 2014, Athlone garda Nick Keogh told the force's confidential recipient, retired judge Patrick McMahon, that senior Garda officers were inflating crime statistics by inducing people to buy drugs from dealers and then sell them to Garda undercover officers, who seized the contraband and reported a crime detected. The then Independent TD Luke Flanagan said Garda Keogh's efforts to have something done resulted in an internal cover-up with the file of an incident about which he complained being "lost" and data removed from the Pulse system.
KEITH HARRISON While serving in Athlone in 2009, Garda Keith Harrison prosecuted a colleague (unsuccessfully) for alleged drink driving, despite opposition from senior officers. Afterwards, he claims, he was subjected to bullying and harassment by colleagues and, despite an unblemished record, to unprecedented scrutiny. This resulted in him facing 16 claims of breaches of discipline, four of which were upheld.
In December 2015, a High Court judge ordered the Garda to abandon an investigation into him for allegedly intimidating his partner, a claim Garda Harrison denied. Earlier in his career, he received a Scott Medal for bravery.
DAVID TAYLOR Superintendent David Taylor is the latest whistleblower to be identified. He claims senior Garda management orchestrated a campaign against Sgt McCabe.
In June 2014, Supt Taylor was transferred from the Garda Press Office to the Traffic Division amid claims he had been involved in illegally disclosing information about a Garda investigation regarding the alleged abduction of two Roma children. He was arrested in May 2015 and questioned about the alleged leaking. Earlier this year, Supt Taylor, who was suspended over a year ago, sought to stop the investigation. The DPP has yet to decide whether to prosecute over the alleged leaking.