Mr Frank Dunlop earns up to £100,000 a year from his shareholding in the Citywest business park in west Dublin, it has emerged.
But although he says he was given £30,000 by the promoters to contribute to politicians, he insists no money was paid to any councillors in connection with the project.
Lawyers for Fianna Fáil senator, Mr Don Lydon, responded by accusing Mr Dunlop of trying to protect his main source of income from the "taint" of corruption.
Mr Dunlop told the tribunal he was given a 2 per cent shareholding in return for lobbying on behalf of a commercial development in 1990. The development, which was not named, is the hugely successful Citywest project.
In 1996/97, he was paid about £200,000 as his share of the proceeds of the sale of a piece of land connected to the development. Since then, he has earned annual dividends varying from £15,000 to £100,000, he said. Dublin city councillors voted by 50-1 to give the go-ahead for Citywest by material contravention in the early 1990s.
Mr Dunlop said he originally agreed a £75,000 fee for his lobbying services but this was "not forthcoming". Instead, he was approached to take a "profit unit" or shareholding. This was for about 2 per cent. He received dividends on this, but the original entity had since been split into three or four and his shareholding had been diluted. Mr Dunlop said that, having advised the promoters to provide him with money for election contributions to politicians, he received £20,000 in 1991 and £10,000. The money went into "a general fund that was available to me" for making payments to politicians.
He estimated that the total amount of money available to him in this fund around this time was about £300,000. On request by the tribunal, he wrote down the names of each client and the sum of money contributed; the total at the end of this exercise came to £457,000.
He repeated on a number of occasions that there were no "disbursements" in relation to this development but admitted he "couldn't answer specifically" for what happened to the money.
Mr Seamus Ó Tuathail SC, for Senator Lydon, accused Mr Dunlop of a "malign mis-recollection" aimed at protecting his income stream.
The witness told counsel that his company, Frank Dunlop and Associates, earned about £3,500 a month last year. In addition to this, he earned about £50,000 to £60,000 from investments.
After Mr Dunlop inadvertently named Citywest while giving evidence, tribunal counsel asked the press not to mention the company's name. However, the company involved was already identified in this newspaper last week.
