http://www.inis.gov.ie/en/INIS/Pages/WP11000014:
Notwithstanding the provisions of section 15, the Minister may, in his or her absolute discretion, grant an application for a certificate of naturalisation to the non-national spouse or civil partner of an Irish citizen if satisfied that the applicant—
is of full age,
is of good character,
and that citizen—
(i) are married to each other, have been married to each other for a period of not less than 3 years, and are living together, as attested to by affidavit submitted by the citizen to the Minister in the prescribed form, or
(ii)are civil partners of each other, have been civil partners of each other for a period of not less than 3 years, and are living together, as attested to by affidavit submitted by the citizen to the Minister in the prescribed form,
is, in the case of a spouse, in a marriage recognised under the laws of the State as subsisting,
had, immediately before the date of the application, a period of one year’s continuous residence in the island of Ireland,
had, during the 4 years immediately preceding that period, a total residence in the island of Ireland amounting to 2 years,
intends in good faith to continue to reside in the island of Ireland after naturalisation, and
has, before a judge of the District Court in open court, in a citizenship ceremony or in such manner as the Minister, for special reasons, allows—
made a declaration, in the prescribed manner, of fidelity to the nation and loyalty to the State, and
undertaken to faithfully observe the laws of the State and to respect its democratic values.