While the Bilingual Education Act underwent multiple reauthorizations and affected the outcome of many court cases at both the state and federal levels [see Wikipedia], the 1994 reauthorization under the Clinton administration was most important for language policy because it reversed “the march away from primary language instruction” [Source], gave preference to grant applications that developed bilingual proficiency in schools, and provided for indigenous languages. For a thorough but brief overview of Bilingual Education, see Ester de Jong here.
