S.D. Codified Laws § 12-18-9
Any candidate, party, or ballot question committee may have poll watchers present at a polling place for the purpose of observing the voting and counting process. During voting hours, a candidate who is on the ballot being voted on may not serve as a poll watcher and may only be present at a polling place to cast the candidate's vote.
Members of the public may observe the voting and counting process at any polling location in a manner that does not interfere with the duties of the poll workers or poll watchers. Each polling place must be arranged in a manner that permits each poll watcher and observer to be positioned in a location where the poll watcher and observer may plainly see and hear what is done within the polling place.
A violation of this section by either a poll watcher, observer, or a poll worker is a Class 2 misdemeanor.
SDCL 12-18-9