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 Pennsylvania, legal immunity from suit or liability in civil litigation and from prosecution in criminal cases is recognized in various forms. Judicial immunity in PA provides judges and other court officials with protection from liability for acts performed in the exercise of their judicial functions. Witness immunity is granted to witnesses who testify in court, protecting them from being sued for their testimony. Diplomatic immunity, which is governed by federal law and international treaties, shields foreign diplomats from civil and criminal jurisdiction of the host country's courts. Governmental or sovereign immunity in Pennsylvania generally protects state and local government entities and their employees from being sued for discretionary actions taken in the course of their official duties, although there are exceptions where the government has waived immunity, such as in cases of vehicle accidents caused by government employees. It's important to note that the specifics of these immunities can be complex and may be subject to certain conditions and limitations.