A more thorough explanation:

rex non potest peccare

Rex non potest peccare is a Latin legal maxim that means "the king can do no wrong." This principle developed into the doctrine of sovereign immunity, which is also known as governmental immunity. The idea behind this principle is that the king, or sovereign, cannot commit a legal wrong. The doctrine of sovereign immunity prevents sovereigns, including the government or its branches, departments, and agencies, from being sued without their consent.

In the United States, sovereign immunity applies to federal and state governments, but not to municipalities. However, federal and state governments have the right to waive their sovereign immunity.

An example of rex non potest peccare in action is when a citizen tries to sue the government for damages caused by a government employee. If the government does not give its consent to be sued, the case will be dismissed due to sovereign immunity.

Another example is when a state government is sued for violating a citizen's constitutional rights. If the state government does not waive its sovereign immunity, the case will be dismissed.

These examples illustrate how the principle of rex non potest peccare has evolved into the doctrine of sovereign immunity, which protects the government from being sued without its consent.