, ▁or ▁that ▁the ▁I RS ▁is ▁not ▁mentioned ▁in ▁the ▁stat utes , ▁or ▁that ▁the ▁I RS ▁has ▁no ▁authority ▁in ▁the ▁absence ▁of ▁established ▁internal ▁re venue ▁" d istrict s ," ▁or ▁that ▁the ▁I RS ▁has ▁no ▁authority ▁outside ▁the ▁District ▁of ▁Columbia . ▁ ▁Arg uments ▁that ▁the ▁I RS ▁is ▁not ▁a ▁government ▁ag ency ▁ ▁Many ▁tax ▁protest ers ▁claim ▁that ▁because ▁the ▁In ternal ▁Re venue ▁Service ▁itself ▁was ▁not ▁created ▁by ▁stat ute ▁and ▁because ▁the ▁I RS ▁has ▁no ▁legal ▁capacity ▁to ▁sue ▁or ▁be ▁su ed , ▁the ▁I RS ▁is ▁not ▁a ▁federal ▁government ▁ag ency . ▁Some ▁claim ▁it ▁is ▁a ▁Puerto ▁R ican ▁trust . ▁O thers ▁claim ▁that ▁the ▁I RS ▁does ▁not ▁law fully ▁exist . ▁The ▁courts ▁have ▁uniformly ▁rejected ▁such ▁arguments . ▁As ▁explained ▁below , ▁the ▁" Internal ▁Re venue ▁Service " ▁is ▁referred ▁to ▁in ▁stat utes ▁and ▁reg ulations ▁as ▁an ▁" ag ency ," ▁as ▁a ▁" b ureau ," ▁and ▁as ▁an ▁" admin istr ative ▁unit " ▁of ▁the ▁U . S . ▁Department ▁of ▁the ▁Tre as ury . ▁ ▁Although ▁the ▁I RS , ▁as ▁a ▁b ureau ▁within ▁the ▁Tre as ury ▁Department , ▁was ▁not ▁created ▁by ▁stat ute ▁( and ▁no ▁law ▁requires ▁that ▁the ▁I RS , ▁as ▁a ▁b ureau ▁within ▁an ▁executive ▁department , ▁be ▁" created " ▁by ▁stat ute ), ▁the ▁United ▁States ▁Supreme ▁Court , ▁in ▁Ch