Counsel for Noirin O’Sullivan at the O’Higgins Commission says his conscience is clear when it comes to challenging the motivation and credibility of Maurice McCabe.

Colm Smyth said he would do it again, despite knowing what he did now about what he has gone through personally since.

Mr Smyth represented the former Garda Commissioner at the O’Higgins inquiry, where he admitted challenging - but not attacking - the motivation and credibility of Sgt McCabe.

The Disclosures Tribunal wants to establish whether Ms O'Sullivan relied on unjustified grounds to discredit the whistleblower at the inquiry.

Mr Smyth said he was never instructed to challenge Sgt McCabe’s character, but said he had to examine his motivation and credibility in relation to allegations if there was no evidence to back them up.

Counsel for McCabe said it was wrong to challenge credibility and motivation, but Mr Smyth said he had a duty to act in the best interests of his clients – and were he asked to do it again he would, despite what he had been through personally since.

Colm Smyth said he fell on his sword for no person, and he abided by his instructions fully when asked to test the credibility of the allegations made by Sgt McCabe.