Minn. R. Crim. P. 18.01
Subd. 1. When Summoned. The court must order that one or more grand juries be drawn at least annually. The grand jury must be summoned and convened whenever required by the public interest, or whenever requested by the county attorney.
On being drawn, each juror must be notified of selection. The court must prescribe by order or rule the time and manner of summoning grand jurors. Vacancies in the grand jury panel must be filled in the same manner as this rule provides.
Subd. 2. How Selected and Drawn. Except as provided for St. Louis County, the grand jury must be drawn from a list composed of the names of persons selected at random from a fair cross-section of the statutorily qualified residents of the county.
In St. Louis County, a grand jury list must be selected from residents of each of the 3 districts of St. Louis County. When the offense is committed nearer to Virginia or Hibbing than to the county seat, the case must be submitted to the grand jury in Virginia or Hibbing.
Minn. R. Crim. P. 18.01