Minn. Stat. § 578.18: DEGREE OF BURDEN OF PROOF.

The burden of proof is on the party bringing the action to declare the absentee dead. If there is a showing that the absentee was exposed to a specific peril at the time of disappearance the burden of proof shall be by a fair preponderance of the evidence. If the absentee was in no unusual danger or peril at the time of disappearance, the burden of proof shall be by clear and convincing evidence.