ister ▁was ▁selected ▁as ▁Spe aker ▁of ▁the ▁Oregon ▁House ▁for ▁the ▁ 1 9 4 3 ▁legisl ative ▁session . ▁During ▁World ▁War ▁II ▁he ▁was ▁a ▁United ▁States ▁Army ▁captain . ▁ ▁In ▁ 1 9 4 8 , ▁he ▁won ▁election ▁to ▁the ▁Oregon ▁State ▁Senate , ▁and ▁served ▁in ▁that ▁chamber ▁during ▁the ▁ 1 9 4 9 ▁session . ▁Also ▁in ▁ 1 9 4 8 , ▁and ▁again ▁in ▁ 1 9 5 2 , ▁William ▁M . ▁Mc All ister ▁was ▁a ▁delegate ▁from ▁Oregon ▁to ▁the ▁Republican ▁National ▁Convention , ▁with ▁his ▁wife ▁serving ▁as ▁an ▁alternate ▁in ▁ 1 9 4 8 . ▁From ▁ 1 9 4 8 ▁to ▁ 1 9 5 1 ▁he ▁was ▁on ▁the ▁Oregon ▁State ▁Bar ' s ▁board ▁of ▁govern ors , ▁followed ▁by ▁the ▁state ▁bar ▁exam in ers ▁board ▁from ▁ 1 9 5 4 ▁to ▁ 1 9 5 6 . ▁ ▁On ▁August ▁ 2 4 , ▁ 1 9 5 6 , ▁William ▁M . ▁Mc All ister ▁was ▁appointed ▁to ▁the ▁Oregon ▁Supreme ▁Court ▁as ▁an ▁associate ▁justice . ▁Oregon ▁Governor ▁El mo ▁Smith ▁appointed ▁him ▁to ▁replace ▁Earl ▁C . ▁Lat ou ret te . ▁Later ▁that ▁year ▁Mc All ister ▁won ▁election ▁to ▁a ▁full ▁six - year ▁term . ▁In ▁ 1 9 5 9 , ▁he ▁was ▁chosen ▁by ▁his ▁fellow ▁just ices ▁to ▁serve ▁as ▁Chief ▁Justice ▁of ▁the ▁court . ▁He ▁served ▁in ▁this ▁role