A Government plan to freeze the property tax may not be legal.
Finance minister Michael Noonan suggested last month the rate could be fixed at 2013 levels until the year 2019.
But according to the Irish Examiner, accountants believe the move could face a legal challenge similar to that mounted in the 1980s over the old property tax.
Director of Chartered Accountants Ireland Brian Keegan said using property valuations from May 2013 for the next four years will cause problems when house prices go up.
He also warned that we could see homes marketed as pre-2013 to keep down tax payments.
Finance Minister Michael Noonan signalled last month that property valuations from May 2013 will be used for an extended period to calculate annual property tax bills, before being replaced by a new property tax in 2019, at the earliest.
But Mr Keegan said all sorts of anomalies will likely arise, including new housing developments attracting higher tax valuations than neighbouring long-established properties.
Such anomalies raise the risk of a homeowner mounting a constitutional challenge, he said.