A few months ago, I attended a 40 hour medical interpretation course. One of the things I learned there is that you should always speak in the first person when interpreting. They explained that if you speak in the third person it puts a gap between the provider and the patient. Also, you, as the interpreter, are a conduit for communication. Your existence should not be relevant to the conversation. You are the voice of the speaker.
However, the thing that blew my mind when I started researching it is that that is common practice. Most sites say that you should never use the first person in interpreting, even in business or legal. The sites listed many of the same reasons. Still, I live in a fairly big city and every time I speak in the first person, the listener looks at me like they have never heard anyone do that. This makes me think that either most interpreters are not trained or most people don’t work with interpreters.
Even in my current job, they don’t hire anyone as a flat-out interpreter. They hire bilinguals into other positions (I am technically a secretary, but what I do is translate). It makes sense that, if that is your practice, you would not be getting good quality interpretation and therefore would not be used to it.
Here is one of the discussions I was reading, if anyone is interested: