S.D. Codified Laws 20-9-4.4
Liability: Use of AED
An individual who, in good faith, uses, attempts to use, or does not use an AED when providing emergency care will not be held legally responsible for any injury suffered by an individual receiving emergency care.
Liability of person using or not using AED
Any person, who in good faith obtains, uses, attempts to use, or chooses not to use an AED in providing emergency care or treatment, is immune from civil liability for any injury as a result of such emergency care or treatment or as a result of an act or failure to act in providing or arranging such medical treatment.