There are some limitations when it comes to interpreter activities in a courtroom.  And it's important for not only a judge to know, but it's also important for the lawyers and for the litigants to know.  And actually jurors when they are interpreting for a juror.  The important thing is that an interpreter is not supposed to express opinions about the case.  They're not supposed to offer advise to litigants or to jurors.  They're not supposed to participate in the deliberations, and a judge needs to know that.

The best way for you to, as a judge, to handle all this is for you to have an open communication with the interpreter before the proceedings.  You want to have a discussion with them to see how you as a judge can make their job more effective and more efficient.  You want the lawyers to be involved.  You want the lawyers to explain to the litigants also that the interpreters job is simply to interpret what is asked or what is said in a court room.  Their job is not to give advice.  Their job is not to independently read some document to the client.  What it's, their limitation is interpretation, that's all it is.

And if you have this conversation in advance of the proceedings then it will be known what the limitations are for the court interpreter. 

NM Court Intepreter Code of Professional Responsibility