Rule 318 Disqualification of Magistrate Judge.

A magistrate judge can't handle a case if they have a personal stake in the outcome or a close family connection to someone involved. This means they must step aside if they're a party to the case, have a strong personal interest in how it turns out, or are related by blood or marriage to one of the parties (or to an officer of a company that's a party) within three degrees of relation. Third degree relatives include people like great-grandparents, great-grandchildren, aunts, uncles, nieces, and nephews, along with closer relatives.

A magistrate judge also can't hear a case if they previously worked as a lawyer for one of the parties, either in this same case or in an earlier case dealing with the same issues. This prevents someone from switching from advocate to judge on matters they already have a stake in.

Finally, a magistrate judge must step aside if there's a real chance that bias or prejudice would prevent a fair hearing. This applies even if none of the other specific situations apply. The goal is simple: everyone deserves a judge who can look at their case without any built-in reason to favor one side over the other.