Justices of the peace are judges who handle both civil and criminal cases, including small claims court, justice court, and administrative hearings. In practical terms, these are lawsuits over debts, evictions, car accidents, unlawful towing, and property.

Their criminal workload involves disposing of all class C criminal misdemeanor complaints, such as traffic citations, issuance of bad check, and others. These cases involve payment, setting contested cases for trial, and pretrial hearings with the county prosecutor.

Other duties include presiding over peace bond hearings, reviewing applications for mental health or chemically dependent commitments, conducting compulsory school attendance trials, and giving warnings to juveniles required by law. They issue warrants for and conduct hearings concerning seizure and disposition of cruelly treated animals. Most justices of the peace perform marriage ceremonies as well.

In Michigan, justices of the peace do not exist as they do in some other states. Instead, Michigan has a system of district courts that handle many of the matters that justices of the peace would in other jurisdictions. District court judges in Michigan preside over civil cases involving claims up to $25,000, landlord-tenant disputes including evictions, small claims (up to $6,500), and land contract forfeitures. They also handle criminal cases including misdemeanors punishable by up to one year in jail, preliminary examinations in felony cases, traffic violations, and other civil infractions. District courts also conduct marriage ceremonies. For issues related to mental health or chemical dependency commitments, these matters are typically handled by probate courts in Michigan. The probate courts also deal with cases involving the treatment of animals and compulsory school attendance. It's important to note that while district court judges may perform some functions similar to those of justices of the peace, they are not the same position and do not have the same title.