S.D. Codified Laws § 23A-22-9 (2026)
A party who intends to raise an issue concerning the law of a foreign country shall give reasonable written notice. A court, in determining foreign law, may consider any relevant material or source, including testimony, whether or not submitted by a party or admissible under rules of evidence. The court's determination shall be treated as a ruling on a question of law.
Source: SL 1978, ch 178 , § 293.