18.—If any question arises as to whether a person held ministerial office before the 6th day of December, 1922, or as to the period during which a person who held a ministerial office before that date held that office, the question shall be referred to a committee consisting of three persons, namely—

(a) the Taoiseach or some person nominated by him,

F69[(b) either—

(i) where there is in Dáil Éireann one qualified Party within the meaning of Part III of this Act and not more, the Leader of that Party, or

(ii) where there are in Dáil Éireann two or more qualified Parties within that meaning and not more, the Leader of that one of those Parties which is of the greater numerical strength in Dáil Éireann, or

(iii) where there are in Dáil Éireann three or more such qualified Parties, the Leader of that one of those Parties which is of the greatest numerical strength in Dáil Éireann,

or a person nominated by such Leader,]

(c) the Chairman of Dáil Eireann or some person nominated by him,

and the decision of such committee on such question shall be final and conclusive and binding on all persons and tribunals whatsoever.