Environment Minister John Gormley has confirmed that he made a mistake in appointing a Fianna Fáil councillor from Donegal and a Green party councillor from Monaghan to the board of the Private Residential Tenancies Board earlier this year.
The act setting up the body precludes local authority members from appointment.
Minister Gormley confirmed that 120 decisions made by the PRTB - the State body that referees landlord-tenant disputes - had to be reviewed as a result of the appointments.
He told Labour's Ciaran Lynch that the provision in the act barring councillors from membership of the board had been overlooked when the appointments of Vincent Martin and Dessie Larkin had been made.
The two councillors were told in September that they were not eligible for membership.
Mr Lynch had alleged the problems stemmed from what he called incompetent cronyism, but Mr Gormley said he would take no lectures on that subject from a party that was well versed in the practice.