Minn. Stat. § 160.845: RESTRICTIONS ON TOLL FACILITY.

(a) A road authority, including the governing body of a city, or a private operator may not convert, transfer, or utilize any portion of a highway to impose tolls or for use as a toll facility. A road authority, including the governing body of a city, or a private operator may not limit operation of a commercial motor vehicle, as defined in section 169.011, subdivision 16, to a toll facility or otherwise require that a commercial motor vehicle use the tolled portion of a highway.

(b) This section does not apply to (1) any toll facility or high-occupancy vehicle lane constructed, converted, or established before September 1, 2007, (2) any additional lane, including a priced dynamic shoulder lane, high-occupancy vehicle lane, or high-occupancy toll lane, added to a highway after September 1, 2007, and (3) any other general purpose lane that adds capacity.