The former TD was the only party to respond to the opening statement of tribunal lawyer, John Gallagher SC. In a 40-minute response, he launched a concerted attack dismissing Mr Gilmartin's allegations and questioning his credibility.
Mr Lawlor contended: "[Mr Gilmartin] is sitting in the middle of the glasshouse here in the tribunal.
"By the time we are finished there will not be many panes of glass left. I hope that the splinters do not inflict too many wounds on him."
Mr Lawlor disputed Mr Gilmartin's account of how they had first met, and completely denied he had "gatecrashed" a meeting of Arlington the British development company backing Mr Gilmartin's projects for Bachelors Walk and Quarryvale (now the Liffey Valley). Nor had he claimed to be the representative of the Irish Government for the project, he said.
Mr Lawlor said his initial interest in the projects were political. He described Bachelors walk as a sick stretch of the quay while "North Clondalkin had no heart or centre or facilities. It was a very grim place".
Taking issue with Mr Gallagher's opening statement, Mr Lawlor claimed both projects had ultimately collapsed not because of political interference or obstacles, as Mr Gilmartin claimed, but because British Aerospace had taken over Arlington Securities and had decided to dispose of its Irish properties.
He also alleged that both projects were significant failures on Tom Gilmartin's behalf, alleging that the "disgruntled and vindictive Tom Gilmartin exited the scheme with £10 million".
"It had nothing to do with the non-cooperation of politicians, interference which officials or politicians delivered, or any effort from Tom Gilmartin to bribe a politician or an official," he said.
Turning to the abandonment of the schemes, Mr Lawlor said: "There is one simple paragraph that sums up the whole module.
"The scheme was brought to an abrupt end in London by British Aerospace who had taken over Arlington. They disposed of properties in Bachelors' Walk.
"It had nothing to do with mafia or monks or £100,000 demands, here there and everywhere."
The former Dublin West TD also focused on a contradiction that has seemingly arisen between various accounts given by Mr Gilmartin of his alleged meeting with senior ministers in Leinster House.
He contended that Mr Gilmartin in one account said he did not know the identity of the man who demanded £5 million of him. And in a later meeting with senior officials from Dublin Corporation, he alleged that man was Mr Lawlor.
"I look forward to questioning him and identifying a pack of lies in his statement," he said.