Mr Liam Lawlor apologised to the Dáil that his actions had brought the House into disrepute but said his non-compliance with the Flood tribunal was in an "unintentional and non-malicious way".
The former Fianna Fáil TD said that "when you think you're slightly more than half right you have to stand up for what you believe".
In an emphatic defence of his actions, he said he hoped to account for every penny he received and that there would be nobody in the witness box making the slightest criticism of corruption against him.
"I have rights the same as everybody else and I feel deeply wounded by what has happened," he said. His family and friends were also deeply wounded.
During his 20-minute address Mr Lawlor sharply criticised the Flood tribunal and said many opposition deputies criticised it privately. He added of the tribunal that "maybe their aggression is because they haven't found what they thought they'd get". He also suggested to the House, that "I really do think you should let the tribunal do the job it was given to do".
He was effusive in his praise of Mr Justice Smyth, who had given him the 28-day prison sentence for contempt. He was "incredibly impressed" with his brilliant intellect and his attention to detail and he accepted his decision with "no criticism".
The Taoiseach was not in the chamber for Mr Lawlor's speech when the Dublin West TD gave deputies the only laugh in the 70-minute-long debate. Referring to his three sons living in the US, he said one worked for a "well-known bank that is in the headlines now. I hope I won't be blamed for that," he said of the AIB fraud in its Maryland subsidiary.
Mr Lawlor referred to "the four Cs - Compliance, criminality corruption and correspondence" - the four main points he wished to make.
"I've already been found to be corrupt but I don't know how," he said. "The media have decided that. I sincerely hope from their point of view, chairman Flood finds that I am, because if I'm not there will be another day" in court. He had a feeling of "swimming against last Friday's tide coming in Dublin Bay". But he believed "the waters will calm and I might get a chance to swim forward".
He added: "I hope that when people come to judge this phase that I will be accountable for every penny I got and that there's nobody down there in that witness box to make the slightest criticism of corruption against Liam Lawlor and I have never ever, and that's what the tribunal was set up for." Referring to his non-compliance, he said there was an early mistake of not understanding or in endeavouring to comply and not complying fully. The courts had rightly found non-compliance "but not non-compliance in an unintentional and not malicious way, because this tribunal has the power to discover so why would you even try to hide anything from them".
Mr Lawlor said he had written to 272 people seeking third-party discovery. When questioned by the tribunal he had refused to answer questions about credit cards because he did not see the purpose of it. That was a "momentous" mistake because it was then perceived as non-compliance with the tribunal.
Apologising for bringing the House into disrepute he said that "when you think you're slightly more than half right, you have to stand up for what you believe and you have to address that matter and you have to address it with whatever tools are available to you".
