Updated: 12.55

The former garda commissioner twice referred to Maurice McCabe as a kiddie fiddler and a child abuser, the Disclosures Tribunal has heard.

Former chairman of the Public Accounts Committee (PAC) John McGuinness has been giving evidence about Sergeant McCabe's and Martin Callinan's dealings with him and the PAC in 2013 and 2014.

The tribunal has heard that there are irreconcilable accounts of a meeting in a hotel car park between John McGuinness and Martin Callinan on January 24th 2014.

Mr McGuinness said malicious rumours about Mr McCabe were doing the rounds of Leinster House in 2013 and 2014, but he chose to ignore them - having met the whistleblower and finding him credible regarding the quashing of penalty points which the PAC was about to look into.

Former Garda Commissioner Martin Callinan is pictured in 2014 | Image: Laura Hutton/RollingNews.ie

The tribunal heard that then-Commissioner Callinan sought and failed to have documents returned to him as he believed they breached data protection acts.

In January 2014, following a robust hearing of the PAC with the Garda Commissioner when he referred to the actions of whistleblowers as 'disgusting', Deputy McGuinness says Martin Callinan referred to whistleblower John Wilson 'pulling a knacker off a horse' on Grafton Street and said Maurice McCabe fiddles with kids - going on to say 'that's the type of f***ing headbangers I'm dealing with'.

The following day, Deputy McGuinness says he met with Commissioner Callinan in a hotel car park when he told him Sergeant McCabe had sexually abused his own family and was not to be trusted - and that he had made a grave error calling him before the Public Accounts Committee.

In a statement to the tribunal, former Commissioner Callinan agrees the meeting took place - but says he only raised his concerns about data protection, and that it was John McGuinness who brought up Maurice McCabe's motivation.