Hennepin County Jury Service. Hennepin County District Court " Phone: (612) 540-7436.All trials must be in the district court. You must complete the paper form located at the bottom of your summons, fill out the questionnaires, and mail them back in the envelope provided. If the defendant fails to waive or demand a jury trial, a jury trial demand must be entered in the record. Subd. 4. Demand or Waiver of Evidentiary Hearing. Learn about the criminal justice process in Hennepin County including investigation, charging, criminal complaint, arraignment, trial, and sentencing. You may file a demand for a jury trial if you want the case to be heard before a jury. Both parties may have attorneys. Jury selection can take anywhere from half a day to a week or more depending on the type of case.