Legal immunity from suit or liability (in civil litigation) or immunity from prosecution (in criminal prosecutions) is a legal status that protects an individual or entity from liability or criminal prosecution. Immunity may be given to the person or entity by law (usually a state or federal statute) or by the agreement of a party to the litigation (usually in the context of a criminal prosecution)—generally for some greater policy goal. Some common types of immunity include (1) judicial immunity; (2) witness immunity; (3) diplomatic immunity; and (4) governmental or sovereign immunity.

In South Dakota, legal immunity encompasses various forms that protect individuals or entities from civil liability or criminal prosecution. Judicial immunity in SD shields judges from liability for acts performed in their judicial capacity, ensuring that judges can perform their duties without fear of personal consequences. Witness immunity may be granted to witnesses in criminal cases to encourage truthful testimony without self-incrimination, often in exchange for cooperation with prosecutors. Diplomatic immunity, governed by federal law and international treaties, protects foreign diplomats from legal action in the U.S., including SD, to promote international relations. Governmental or sovereign immunity generally protects the state of South Dakota and its subdivisions from being sued without their consent, although this immunity can be waived in certain circumstances as prescribed by state law. Each type of immunity serves a specific policy goal, such as the fair administration of justice, the effective gathering of evidence, the maintenance of diplomatic relations, or the protection of government functions.