In what circumstances have courts found an interpreter who was not sworn to be an interpreter at trial?

In People v. Menchaca, supra, at page 1025, 194 Cal.Rptr. 691, the court deemed the omission of the oath to the district attorney's investigator, whom the defendant used in "desperation" as a "stop-gap interpreter," to be "fatal to the constitutional effectiveness of an interpreter." The court held that a third-party witness interpreter cannot insure that a defendant spontaneously understands testimony, court rulings, or discussions between the court and counsel, and that "nothing short of a sworn interpreter at defendant's elbow will" satisfy constitutional requirements. (Id., at p. 1025, 194 Cal.Rptr. 691.)

In People v. Chavez (1981) 124 Cal.App.3d 215, 222-226, 177 Cal.Rptr. 306, the case relied on in Menchaca, it was the "sum" of many factors which caused a finding that the defendant had been deprived of his constitutional right to an interpreter throughout the proceedings. There, the defendant's trial counsel acted as defendant's interpreter on several occasions, but was sworn only once, and the trial court had "reason to question the adequacy of communication between [counsel] and defendant." (People v. Chavez, supra, at p. 226, 177 Cal.Rptr. 306.) At one point, an employee of the district attorney's office acted as an unsworn interpreter. (Id., at p. 223, 177 Cal.Rptr. 306.)