The Supreme Court is due to deliver judgment today in Joan Collins' appeal over the High Court's rejection of her challenge to the promissory notes.
The Independent TD claims the issuing of the controversial IOUs to bail out Anglo Irish Bank and other financial institutions was unconstitutional.
The €31bn promissory notes were issued to allow Anglo Irish Bank and other financial institutions to get emergency funding from the Central Bank.
There was no other source of funding available at the time, so the then Minister for Finance Brian Lenihan drew up the notes with a view to paying the money back in instalments.
Joan Collins challenged them before the High Court but was unsuccessful so she appealed her case to the Supreme Court.
She claims they shouldn't have been issued for a number of reasons, including the fact there wasn't a Dáil vote on them.
Counsel for the State claims the Minister had the power to do what he did under legislation introduced in 2008 to avert a banking collapse.
Following the death of Mr. Justice Adrian Hardiman, the case concluded before a six-judge panel in April. A judgement is due this morning but if there's a split in the decision, the appeal will have to be heard again.