Former garda commissioner Martin Callinan has told the Disclosures Tribunal he never said that whistleblower Sergeant Maurice McCabe was not to be trusted or that he had questions to answer.

Mr Callinan is giving evidence for a second day to the inquiry, which is examining allegations of a smear campaign against Sgt McCabe.

He was questioned about the accounts of three people who claim he spoke negatively about Sgt McCabe during conversations on the day of a Dáil Public Accounts Committee meeting on 23 January 2014.

Mr Callinan was asked about a conversation with the then PAC chairman Fianna Fáil TD John McGuinness, who claims Mr Callinan referred to Sgt McCabe as abusing children, and referred to Sgt McCabe and another whistleblower - retired Garda John Wilson - as "f-ing headbangers".

Mr Callinan claims that Mr McGuinness referred to Mr Wilson as a "header" when Mr Callinan asked the TD if Mr Wilson would be giving evidence to the committee

Mr McGuinness denies this.

The former commissioner told the tribunal that he had never heard an anecdote Mr McGuinness claims Mr Callinan told about Mr Wilson dealing with a horse on Grafton Street.

Counsel for the tribunal, Patrick Marrinan, put it to Mr Callinan that the former Garda Press Officer Supt David Taylor had also given evidence that he had heard Mr Callinan use the term "kiddie fiddler".

Mr Callinan said he had never heard that expression before.

Mr Callinan was asked about the evidence given by the Comptroller & Auditor General Seamus McCarthy, that Mr Callinan told him Sgt McCabe was not to be trusted and that there were allegations of sexual offences against him, during a conversation on the day of the PAC meeting.

Mr Callinan said he never said Sgt McCabe had sexual offences against him and as far as he had been concerned the only allegation was a 2006 allegation against the sergeant that had been dismissed by the DPP.

He said he had told Mr McCarthy about this 2006 allegation to correct the record, after Mr McCarthy indicated he had heard a rumour that Sgt McCabe was being investigated over a sexual allegation.

Mr McCarthy has previously told the tribunal he did not raise any questions of allegations of sexual offences during the conversation.

Mr Callinan was also questioned about evidence given by Fine Gael TD John Deasy, who told the tribunal that before the PAC meeting, Mr Callinan made reference to Sgt McCabe as someone who could not be believed or trusted.

Mr Callinan told the tribunal that he had mentioned that not all of the complaints made by Sgt McCabe about penalty points had turned out to be correct.

However he said he did not say that Sgt McCabe was not to be trusted.

He said he would never use those words about any member of An Garda Síochána.

Mr Callinan also told the tribunal that he is telling the truth and that he did not make derogatory remarks about Sgt McCabe to four individuals around the time of the Public Accounts Committee hearing into penalty points.

Mr Callinan said he accepted that his version of the conversations were at a variance but he said he was clear in his recollections.

TDs John McGuinness and John Deasy, Controller and Auditor General, Seamus McCarthy and solicitor Gerard Kean have all given evidence that in January 2014, Mr Callinan told them Sgt McCabe was not to be trusted or was troublesome or was a child abuser.

Counsel for the tribunal, Patrick Marrinan, suggested to Mr Callinan that taken together with his "disgusting" comment at the PAC, it built up a fairly firm picture that the Garda Commissioner was quite hostile to Sgt McCabe.

Mr Callinan said he did not agree.  Asked why the individuals were lining up against him, he said he did not know if that was the case but he could only provide his own evidence.

He also denied telling John McGuinness in a meeting in a car park that the sergeant abused his own family and an individual.

He said that was absolutely false and he said he would never say anything of that nature.

He said they were outrageously serious allegations and he could not understand why they were being said and he said that they were not true.

He also said he thought there was an "element of fuzziness" around how Mr McGuinness made the allegations and he suggested the TD had contradicted his own account in radio interviews.

Mr Callinan also denied telling Mr McGuiness that "there would be trouble" and he said he was not trying to undermine the work of the PAC.

He said he sought out the meeting with Mr McGuinness because he wanted to resolve the issue over the appearance of Sgt McCabe at the PAC which he was against.

He also said that it was Mr McGuinness who asked whether Sgt McCabe was bringing forward his complaints because of the previous sexual assault allegation made against the sergeant.

Mr Callinan said he was surprised to hear this.

He also said that it was clear that John McGuinness took grave exception to his challenging Sgt McCabe's appearance at the committee.

This afternoon, Mr Callinan told the tribunal he did not order a document to be compiled containing details of HR and disciplinary matters with references to Sgt McCabe for a meeting held to prepare for the PAC meeting in January 2014.

Michael McDowell, counsel for Sgt McCabe, has been cross-examining Mr Callinan about the document, which came under the heading "Reports on Sgt Maurice McCabe and retired Garda John Wilson" and which the tribunal has heard was included in material used in a pre-PAC meeting.

The tribunal also saw correspondence relating to an interview carried out by two senior gardaí with an uncle of Sgt McCabe in 2013.

Mr McDowell put it to Mr Callinan that the investigators were going to speak to Sgt McCabe's uncle because they believed he had information which could be discreditable to the sergeant.

Mr McDowell put it to Mr Callinan that there had been an attitude of deep suspicion and willingness to search records for anything that could assist in damaging Sgt McCabe.

Mr Callinan said that this was certainly not the case from his perspective.

He said he did not know the provenance of the report on Sgt McCabe, and that he could not say whether or not the report was brought to the pre-PAC meeting because he did not recognise it.

Mr Callinan said under no circumstances did he order any document to be compiled in an effort to do down Sgt McCabe, and that "nothing could be further from the truth" than that suggestion.

Mr Callinan has denied that he provided a script for solicitor Gerarld Kean to deliver on an RTÉ radio show.

Under cross examination, Mr McDowell suggested to Mr Callinan that he had given Mr Kean a script during a series of phone calls the day before Mr Kean was due to appear on the Marian Finucane show in January 2014.

Mr Callinan said those are "your words", not mine.

He said Mr Kean asked him for pointers for the programme and Mr Callinan said he told the solicitor that the information was on the internet. He added that he had only passed on information that was in the public domain.

He said he was taken back when he later heard the programme and he agreed that he felt Mr Kean had strayed off a path.

Mr Callinan was also asked about how paragraphs he drafted ended up in a reply that Mr Kean sent to a complaint from Sgt McCabe.

He said he did not specifically direct those points to be put to the sergeant, although he added that it was not his finest hour.

He also denied telling Mr Kean not to reveal that he had been talking to the garda commissioner.

The inquiry has adjourned for today and Mr Callinan will return for further cross examination tomorrow.