: Bus iness people ▁from ▁Kentucky ▁Category : Saint ▁Louis ▁University ▁al umn i ▁Category : 1 9 th - century ▁American ▁business people <0x0A> </s> ▁Che v ron ▁U . S . A ., ▁Inc . ▁v . ▁Natural ▁Resources ▁Def ense ▁Council , ▁Inc ., ▁ 4 6 7 ▁U . S . ▁ 8 3 7 ▁( 1 9 8 4 ), ▁was ▁a ▁land mark ▁case ▁in ▁which ▁the ▁United ▁States ▁Supreme ▁Court ▁set ▁forth ▁the ▁legal ▁test ▁for ▁determ ining ▁whether ▁to ▁grant ▁de ference ▁to ▁a ▁government ▁ag ency ' s ▁interpretation ▁of ▁a ▁stat ute ▁which ▁it ▁admin ister s . ▁The ▁decision ▁art ic ulated ▁a ▁doctrine ▁now ▁known ▁as ▁" Che v ron ▁de ference ". ▁The ▁doctrine ▁consists ▁of ▁a ▁two - part ▁test ▁applied ▁by ▁the ▁court , ▁when ▁appropriate , ▁that ▁is ▁highly ▁de fer ential ▁to ▁government ▁ag encies : ▁" wh ether ▁the ▁ag ency ' s ▁answer ▁is ▁based ▁on ▁a ▁perm iss ible ▁construction ▁[ emph asis ▁added ] ▁of ▁the ▁stat ute ", ▁so ▁long ▁as ▁Congress ▁has ▁not ▁spoken ▁directly ▁to ▁the ▁precise ▁issue ▁at ▁question . ▁ ▁The ▁decision ▁involved ▁a ▁law suit ▁challeng ing ▁the ▁U . S . ▁government ' s ▁interpretation ▁of ▁the ▁word ▁" source " ▁in ▁an ▁environmental ▁stat ute . ▁In ▁ 1 9 7 7 , ▁the ▁U . S . ▁Congress ▁passed ▁a ▁bill ▁that ▁am ended ▁the ▁C lean ▁Air ▁Act ▁of ▁ 1 9