S.D. Codified Laws § 32-2-7
Agents, patrol officers, motor carrier enforcement officers, and motor carrier inspectors of the Department of Public Safety shall assist in the enforcement of all laws, police regulations, and rules governing motor vehicles and motor carriers over and upon the highways of this state. The agents, patrol officers, motor carrier enforcement officers, and motor carrier inspectors may stop any vehicle or carrier to examine, measure, or weigh the vehicle and its load and to withdraw and inspect any fuel being transported by the vehicle or used to propel the vehicle. The agents, patrol officers, motor carrier enforcement officers, and motor carrier inspectors may examine any bill-of-lading, registration, license, or permit to determine if the motor carrier is properly registered, licensed, or permitted and if the load transported is an amount permitted by the commercial motor vehicle license issued to the carrier.
SDCL 32-2-7