S.D. Codified Laws § 15-16-46

In matters concerning defamation, the court, before it recognizes an out-of-country foreign judgment, shall by clear and convincing evidence, find that the law applied in the foreign court's adjudication, which resulted in a judgment, provided at least as much protection for freedom of speech and the press as would be provided by the United States Constitution and the Constitution of the State of South Dakota, in addition to the criteria set forth in § 15-16-45.