The special tax relief deal available to composers, artists and writers has resulted in one multi-millionaire being able to avoid paying tax on up to €10 million earned in just eight months.
New figures from the Revenue Commissioners show 28 artists earning between €500,000 and €10 million claimed exemption on over €46.6 million in earnings in 2001.
The big winners from the scheme are thought to be music millionaires lodging claims for exemption on income from their lyrics and musical compositions.
The tax-free status for artists' and writers' earnings was introduced by former taoiseach Charles Haughey when he was finance minister in 1969. It was intended to show the State valued creative people in society.
Ireland is unique in the world for allowing artists to keep every cent of their earnings, though they do pay PRSI.
When Mr Haughey brought in the scheme there were few high earners here amongst the ranks of the country's writers, playwrights, composers, painters and sculptors.
Since then a number of novelists have written international best-sellers and Irish musical talent has scored major successes. Rock groups like U2, The Corrs, Boyzone, Westlife, singers like Enya, Van Morrison, Chris de Burgh and major shows like Riverdance are making superstar earnings around the world.
The scheme has also helped new writing successes like Cecelia Ahern, daughter of the Taoiseach, Mr Ahern, who claimed for the earnings on her best-selling first novel, PS I love you.
The most recent figures for the cost of the scheme are for the short eight-month tax year in 2001, before the switchover to calendar-year income tax returns.
There were 1,323 claims from artists, involving €80 million in income. Granting the exemptions cost the Exchequer €23.5 million.
It is estimated that the cost of the scheme in the full tax year 2000-01 was €36.8 million, according to figures supplied to Green Party TD Ciaran Cuffe by Finance Minister Mr Cowen.
Mr Cuffe, who is equality spokesman for the Greens, said he believed there should now be a cap on the amount of income tax relief that can be sought.
"This scheme was meant to assist struggling artists but it seems as though the bulk of benefits are now accruing to those on high incomes," he said.
"When you realise that there are 28 people earning an average of over a million each in the scheme I think it is time to look again at it even though most of them are probably my constituents in Dún Laoghaire."
Tax inspectors make their decision on applications using guidelines drawn up by the Arts Council and the Minister for the Arts.