Mont. Code Ann. § 20-10-108

When the trustees authorize a two-way radio as standard equipment on a school bus, the two-way radio may be operated on the same frequency as that used by the Montana highway patrol and the sheriff of the county when their permission and the permission of the federal communications commission is secured. If permission is not secured from these agencies, the frequency assigned by the federal communications commission shall be used for the operation of the two-way radio.