Ex parte communication.
An “ex parte” communication in the law biz, means a communication to the judge in the case, in which no other “side” in the case is involved. The term has different meanings in different contexts.
Some statutes specifically permit one part to go to a judge and request “ex parte” that a certain type of order be issued. For example, the Minnesota statute regarding harassment restraining orders specifically permits that a judge consider one “ex parte” (as long as there is a hearing shortly thereafter with both sides involved).
The improper type of “ex parte” communication means that one side is gaining access to the judge without the other side knowing about it and there is no statute or rule that permits it. A typical type of “ex parte” communication that a party might complain about? One lawyer in a case sends an email to a judge, and does not copy the other side. That means the judge has information from only one side, and does not hear the rebuttal by the other side on the same issue. Of course, “ex parte” communications can also occur in person (in hallways, judge’s offices, cafeterias), by phone or text, and even by relaying a message through another judge.
Lawyers are prohibited from engaging in these improper “ex parte” communications, and judges are as well, see Minnesota Code of Judicial Conduct
RULE 2.9 Ex Parte Communications
(A) A judge shall not initiate, permit, or consider ex parte communications, or consider other communications made to the judge outside the presence of the parties or their lawyers, concerning a pending or impending matter [although some exceptions are listed].