S.D. Codified Laws § 32-28-7
Meaning of flashing red signal--Violation as misdemeanor
If a red lens is illuminated with rapid intermittent flashes, drivers of vehicles shall stop before entering the nearest crosswalk at an intersection or at a limit line when marked, or, if none, then before entering the intersection, and the right to proceed is subject to the laws applicable after making a stop at a stop sign. A violation of this section is a Class 2 misdemeanor.
Source: SL 1963, ch 274, § 3 (1); SL 1989, ch 255, § 190.