Mr George Redmond told the tribunal he was "sorry" about accepting cash payments when he was assistant Dublin city and county manager in the late 1980s.
In particular, he said it was an "understatement" to say he was sorry he received a £25,000 cash payment from Mr James Gogarty of the Murphy group in 1988. "Inappropriate is the right word".
Mr Patrick Hanratty SC, for the tribunal, referred Mr Redmond to rules governing the behaviour of officials of Dublin County Council, called "Rules of Conduct for Officers of Local Authorities". Mr Redmond said he was familiar with them and they existed when money was received.
Mr Hanratty asked him if his actions were appropriate when he considered the regulations.
Mr Redmond replied: "As far as the regulations are concerned I appreciate they were there, and I appreciate that they can be construed in a certain way, and I deeply regret that, if I ever transgressed them, and I did," he said.
"And are you sorry that you did?" asked Mr Hanratty.
"Am I sorry that I did? That is the understatement. Yes, of course I am."
"Do you now accept that some, at least, of the payments were entirely inappropriate, particularly having regard to the specific provisions which are contained in these regulations?"
Mr Redmond agreed they were.
"Having looked at them today, have you changed in any way in your view that it mightn't have been appropriate to have taken the monies which we have been discussing in the last few days?"
Mr Redmond said while accepting £25,000 was inappropriate he got involved in the sale of the Murphy lands because he believed what he was doing had benefits for Dublin County Council.
He was asked about a visit he made to Mr Gogarty's house in August 1997, a period when allegations that a leading local authority official had received a £25,000 cash payment surfaced in newspapers. Mr Gogarty was ill in bed and Mr Redmond was unable to speak to him. He left a note asking Mr Gogarty to contact him but he never did.
Mr Redmond said he went to Mr Gogarty's home to make sure Mr Gogarty was not "bringing me into" rezoning allegations which were also featuring in the media.