The head of the AGSI says he would describe Garda whistleblowers as "brave", "committed" and "strong".
The organisation representing middle-ranking members of the force is gathering for its annual conference this week, and protection for whistleblowers will be among the issues discussed by delegates.
Interim Garda Commissioner Noirin O'Sullivan will address the conference tomorrow, and will take questions from the floor - which organisers say is 'very significant'.
This year will mark the first time the Justice Minister has not addressed the AGSI event.
General Secretary John Redmond says his members are disappointed.
Mr Redmond said: "The Minister's office contacted us last week and said the minister couldn't attend.
"He's observing Passover, which starts today I understand, and he also has a meeting over in Luxembourg tomorrow.
"Our delegates are very disappointed that it can't happen today, we can't do anything but accept those reasons in good faith, but it's a pity."
However, one of the Garda whistleblowers says he has yet to see any change in culture in the force since the Garda Tapes and GSOC controversies.
Garda whistleblower John Wilson says the force needs a major shift in culture, saying more claims of irregularities are being brought to his attention.