US v. Murguia-Rodriguez, No. 14-10400 (3-1-16)(Reinhardt with Tashima; dissent by Callahan).  This an interpreter waiver issue.  A divided 9th panel   vacated and remanded because the district court failed to comply with the procedural safeguards of 28 U.S.C. § 1827(f)(1) when the court dismissed the interpreter.

The district court at sentencing had asked the defendant if he was willing to proceed at sentencing without an interpreter. He said he was, but stated that the interpreter should stand by just in case he had difficulties.  The court pressed him, stating that the interpreter was busy with other duties.  This request by the court, and the acquiescence by the defendant, was not a valid waiver. The court failed to explain the nature and effect of the waiver, and the defendant did not expressly, on the record, agreed to a waiver.  Finding error, the 9th then declines to exercise its discretion in determining whether the error was harmless. The majority finds that the government had waived its harmlessness argument.

Dissenting, Callahan argued that the defendant had not objected, and the majority, by not requiring prejudice, relieves defendant of his burden of showing prejudice. In response to Callahan's argument that plain-error review applies, the majority expressly declines to apply even harmless-error review because the government failed to argue it in its brief.  This holding requires the government to argue harmlessness.

The decision is here:

https://cdn.ca9.uscourts.gov/datastore/opinions/2016/03/01/14-10400.pdf