What is the primary role of a "magistrate judge"?

The primary role of a magistrate judge is to assist in pretrial matters and conduct preliminary hearings. Magistrate judges serve as judicial officers who handle various duties to help streamline the legal process. They often manage cases in the early stages, which can include setting bail, conducting arraignments, overseeing pretrial motions, and holding preliminary hearings to determine whether there is enough evidence for a case to proceed to trial. By performing these functions, magistrate judges play a crucial role in the efficiency of the judicial system, allowing district judges to focus on trials and more complex legal matters.

The other options involve roles that are typically reserved for district judges or other legal representatives. For example, presiding over jury trials is not a responsibility of a magistrate judge, as trials are conducted by district judges. Similarly, providing rulings on constitutional issues usually falls within the jurisdiction of higher courts where significant legal interpretations are needed. Representing the government in criminal cases is a role designated for prosecutors rather than judicial officers.