Minn. Stat. § 634.07
If a person, in any state which by its laws has made provision for commanding persons within that state to attend and testify either for the prosecution or the defense in criminal actions, or for the purpose of a grand jury investigation which has commenced or is about to be commenced, in this state, is a material witness in an action pending in a district court, or a grand jury investigation which has commenced or is about to be commenced, in this state, a judge of such court may issue a certificate, under the seal of the court, stating these facts and specifying the number of days the witness will be required. This certificate shall be presented to a judge of a court of record in the county in which the witness resides, or the county in which the witness is found if not a resident of that state.
If the witness is ordered by the court to attend and testify in a criminal action or a grand jury investigation in this state the witness shall be tendered the sum of ten cents a mile for each mile by the ordinary traveled route to and from the court where the action is pending, or the place where the grand jury investigation has commenced or is about to be commenced, and $5 for each day that the witness is required to travel and attend as a witness. A witness who has appeared in accordance with the provisions of the order of the court shall not be required to remain within this state a longer period of time than the period mentioned in the certificate.
Minn. Stat. § 634.07
(9819-2) 1935 c 140 s 2; 1955 c 812 s 2; 1986 c 444