§ 4.35 (B)
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(B) Court as Interpreter. Because of the incompatibility of the roles of interpreter and judge, the court should never serve as interpreter. In fact, it is improper for a judge to communicate with anyone on the record (or, arguably, even off the record in connection with a case) in any language other than English, as this is equivalent to an ex parte communication to which other participants in the process are not privy since they do not understand the foreign language the court is using. “It is strongly recommended that direct communication between a judge and a witness or a party to the case in that person’s source language be avoided, unless an interpreter is present to interpret the communication into English for all other participants in the courtroom. This is important because a judge’s communication may create a perception of bias, and also because it may constitute ex parte communications where the attorney or party cannot communicate in the same source language.
 Court Interpreters in Criminal Proceedings: Appointment, Qualification and Effective Utilization, Chap. 6 in American Bar Ass’n Comm’n on Immigration, Judicial Immigration Education Project, A Judge’s Guide to Immigration Law in Criminal Proceedings 6-9 to 6-10 (P. Goldberg & C. Wolchok, eds., 2004).