As has been widely noted, the Constitution says –
The State shall not be bound by any international agreement involving a charge upon public funds unless the terms of the agreement shall have been approved by Dáil Éireann.
The current talking points supplied by the government’s ace legal department are that since the loan program is only a facility that doesn’t have to be used, it’s not a charge on public funds. But as with the government position on bank bondholders, it’s really not hard to find contradictory information. The agreement with the IMF — the ‘I’ in IMF standing for international — is under the Extended Fund Facility (EFF). And like its companion Standby Arrangement (the one that Greece currently has), here’s the fee structure –
resources committed under all EFFs are subject to a commitment fee levied at the beginning of each 12-month period on amounts that could be drawn in the period (15 basis points for amounts up to 200 percent of quota, 30 basis points on amounts between 200 and 1,000 percent of quota, and 60 basis points on amounts exceeding 1,000 percent of quota). These fees are refunded if the amounts are borrowed during the course of the relevant period.
In other words, money will be paid to the IMF regardless of whether the facility is used. There is a charge on public funds. The historical irony is that Eamon De Valera liked this clause because he had used the underlying legal principle to argue that the Free State wasn’t obliged to pay the land annuities. His successors are now trying — with some very 3rd rate lawyering — to dodge around it.
UPDATE: Here’s the 1957 Act under which Ireland joined the IMF. I can’t tell if the references to payments that the legislation allows under the Fund Articles of Agreement include the charges that the government would now have under the EFF.