British Nationality Act 1981

31 Continuance as British subjects of certain former citizens of Eire

(1) A person is within this subsection if immediately before 1st January 1949 he was both a citizen of Eire and a British subject.

(2) A person within subsection (1) who immediately before commencement was a British subject by virtue of section 2 of the 1948 Act (continuance of certain citizens of Eire as British subjects) shall as from commencement be a British subject by virtue of this subsection.

(3) If at any time after commencement a citizen of the Republic of Ireland who is within subsection (1) but is not a British subject by virtue of subsection (2) gives notice in writing to the Secretary of State claiming to remain a British subject on either or both of the following grounds, namely—

(a) that he is or has been in Crown Service under the government of the United Kingdom ; and

(b) that he has associations by way of descent, residence or otherwise with the United Kingdom or with any dependent territory,

he shall as from that time be a British subject by virtue of this subsection.

(4) A person who is a British subject by virtue of subsection (2) or (3) shall be deemed to have remained a British subject from 1st January 1949 to the time when (whether already a British subject by virtue of the said section 2 or not) he became a British subject by virtue of that subsection.