Minn. Stat. § 86B.601
Subd. 1. Flag required.
Subd. 2. Group diving.
Subd. 3. Light required for night diving.
A person may not scuba or skin dive in waters of this state from one hour after sunset to sunrise on the following day unless the diver has in possession a diver's light that is visible from above the water at a distance of at least 150 feet, except that a diver's light is not required in an emergency, salvage, repair, or construction operation.
Subd. 4. Night diving with spear prohibited.
A person may not scuba or skin dive while in possession of a spear from sunset to sunrise.