il ▁was ▁open ▁to ▁all ▁citizens ▁who ▁had ▁reached ▁the ▁age ▁of ▁twenty - one . ▁However ▁those ▁who ▁were ▁leg ally ▁dis qual ified ▁or ▁who ▁were ▁members ▁of ▁the ▁Se an ad ▁were ▁ex cluded . ▁For ▁most ▁of ▁the ▁period ▁of ▁the ▁Irish ▁Free ▁State ▁the ▁constitution ▁also ▁contained ▁a ▁controvers ial ▁requirement ▁that ▁all ▁members ▁of ▁the ▁O ire acht as ▁swe ar ▁an ▁o ath ▁of ▁f idel ity ▁to ▁the ▁King , ▁as ▁well ▁as ▁an ▁O ath ▁of ▁Al leg iance ▁to ▁the ▁constitution ▁of ▁the ▁Free ▁State . ▁The ▁o ath ▁was , ▁however , ▁abol ished ▁by ▁a ▁constitution al ▁am end ment ▁in ▁ 1 9 3 6 . ▁ ▁The ▁D á il ▁was ▁elected ▁on ▁the ▁basis ▁of ▁universal ▁adult ▁suff rage ▁by ▁" pro port ional ▁representation " ▁and ▁the ▁Single ▁Transfer able ▁V ote . ▁However ▁the ▁franch ise ▁was ▁restricted ▁to ▁those ▁over ▁twenty - one . ▁As ▁adopted ▁the ▁constitution ▁required ▁that ▁a ▁D á il ' s ▁term ▁would ▁last ▁for ▁four ▁years , ▁unless ▁the ▁law ▁specified ▁a ▁shorter ▁period ▁or ▁the ▁house ▁was ▁dissol ved ▁early . ▁However , ▁after ▁changes ▁to ▁the ▁constitution ▁and ▁the ▁law ▁in ▁ 1 9 2 7 , ▁the ▁constitution al ▁maximum ▁became ▁six ▁years , ▁and ▁the ▁legal ▁maximum ▁five . ▁The ▁D á il ▁could ▁theoret ically ▁have ▁been ▁dissol ved ▁at ▁any ▁time ▁by ▁the ▁King , ▁acting ▁on ▁the ▁advice ▁of ▁Executive ▁Council ,