District Court judge's recognition at sentencing of a language barrier did not undercut the court's finding that an earlier waiver of jury trial and guilty plea had been knowing and voluntary, despite the deft's claim that simultaneous translation had made the proceedings impossible to follow. (Also given a written form.)
http://media.ca8.uscourts.gov/opndir/18/06/172431P.pdf
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.