, ▁Rat ul ang i ▁continued ▁to ▁ag itate ▁for ▁equal ▁rights ▁and ▁advoc ating ▁Indones ian ▁national ism ▁by ▁align ing ▁himself ▁with ▁the ▁National ist ▁C au cus ▁( F rak si ▁K eb ang sa an ) ▁that ▁was ▁started ▁by ▁Moh amm ad ▁Hus ni ▁Th am rin . ▁He ▁was ▁a ▁co - sp ons or ▁of ▁the ▁So et ard jo ▁Pet ition , ▁which ▁expressed ▁the ▁desire ▁for ▁an ▁independent ▁state ▁through ▁grad ual ▁re forms ▁within ▁a ▁ten ▁year ▁period . ▁The ▁pet ition ▁passed ▁the ▁Volks ra ad , ▁but ▁was ▁not ▁accepted ▁by ▁the ▁colonial ▁government . ▁This ▁response ▁to ▁the ▁pet ition ▁led ▁to ▁the ▁formation ▁of ▁G API ▁( des cribed ▁earlier ). ▁Rat ul ang i ▁was ▁not ▁hes it ant ▁to ▁critic ize ▁the ▁authorities ▁and ▁would ▁eventually ▁be ▁considered ▁a ▁risk ▁to ▁them . ▁He ▁continued ▁to ▁serve ▁in ▁the ▁Volks ra ad ▁until ▁ 1 9 3 7 , ▁when ▁he ▁was ▁arrested ▁due ▁to ▁his ▁increasing ▁political ▁views . ▁He ▁was ▁ja iled ▁for ▁several ▁months ▁in ▁Su k am isk in ▁in ▁Band ung . ▁ ▁In ▁ 1 9 3 2 , ▁Rat ul ang i ▁was ▁one ▁of ▁the ▁found ing ▁members ▁of ▁the ▁United ▁Sch ol ars ▁of ▁Indones ia ▁( V eren ig ing ▁van ▁Indones ische ▁Academ ici ). ▁He ▁was ▁also ▁part ▁of ▁a ▁group ▁of ▁church ▁leaders ▁and ▁national ists ▁( including ▁B . W . ▁Lap ian