The legal doctrine of sovereign immunity limits the circumstances under which a private person or entity (a nongovernmental unit) may sue a state government or the federal government. Sovereign immunity in the United States was derived from the English common law policy (from Great Britain) that the king (the sovereign) could do no wrong and should not be held to account by his subjects (the people).

Current legal theory also relies on sovereign immunity to protect the public treasury (the fisc) from unlimited claims.

Many states have laws (statutes) known as tort claims acts that waive the government’s immunity in whole or in part for certain specified claims and allow private parties (persons or entities) to sue the government for torts (wrongful acts) committed by persons acting on behalf of the government. In some instances, tort claims acts waive sovereign immunity for claims against the government for personal injuries (as well as for property damage).

And the U.S. Congress has passed a law (a statute) known as the Federal Tort Claims Act that waives the federal government’s immunity for certain claims and allows private parties (persons or entities) to sue the federal government for torts (wrongful acts) committed by persons acting on behalf of the federal government. The Federal Tort Claims Act is located in the United States Code, beginning at 28 U.S.C. §2674.

Lawsuits against the federal government under the Federal Tort Claims Act must be filed in federal courts in the United States.

In Arizona, as in other states, the legal doctrine of sovereign immunity means that the state and its subdivisions are generally immune from being sued unless they have consented to the lawsuit. This principle is rooted in the idea that the government cannot be sued without its consent, which is a concept inherited from English common law. However, Arizona has enacted the Arizona Tort Claims Act, which waives sovereign immunity in certain situations, allowing individuals to bring claims against the state or its employees for acts of negligence or other wrongful acts committed within the scope of their employment. Similarly, at the federal level, the Federal Tort Claims Act (FTCA) allows for certain types of lawsuits against the United States government for wrongful acts committed by federal employees during their employment. Claims under the FTCA must be filed in federal court. It's important to note that both the Arizona Tort Claims Act and the FTCA have specific procedures and limitations that must be followed when bringing a claim.