Here the same about many people, for instance, those came from China, Korea or Laos, who are accused not only of speaking 'unintelligible' languages but of keeping 'expressionless' faces in order to complete the offense of being hard workers.
I remember how I learnt it at school: Is it legal here a signed contract written in Swahili and Burukashi? Yes, totally. So no language is mandatory except for formal occasions. But still only recently it was allowed to the original people to have official education in their languages -but not exclusively-. But they are sending Gypsy children to the public school in Spanish and they forced Mennonite children to follow part of their education in Spanish, because Spanish is considered the language everybody must know to understand their rights and obligations with the rest of their fellow country people.
I suppose something similar in the States.