Thanks Brenda and Cathryn,
the Atty Gen had asked about the 'swearing in for sign language' so we were just trying to see if anyone 'knew' a specific one, lol! I was thinking the Interpreter one is perfectly fine. The CR may have not used "Mr./Madam Interpreter" in their wording tho. Not sure.
I really hope I'm doing it right. I'm in California, FWIW. I just say, "Mr./Madam Interpreter, please raise your right hand.
"Do you solemnly promise to translate all of the questions, answers, and colloquy in this proceeding from English to (other language) and (other language) to English fully and accurately?"
Sometimes the interpreter will add, "To the best of my ability," which is fine unless the lawyers have a problem with it (haven't run across this yet). It might seem unusual to include colloquy in that my oath, but I once had an interpreter who didn't interpret anything but questions and answers. Not my place to say anything, but it didn't seem right to me.
If it's American Sign Language, I just say, "Do you swear to interpret the testimony in this deposition from American Sign Language into English and English into American Sign Language to the best of your ability?"