Jowitt's Dictionary of English Law describes public law as having several branches, as follows:
"... law is either public or private.
"Public law is that part of the law which deals with the state, either by itself or in its relations with individuals, and is called constitutional, when it regulates the relations between the various divisions of the sovereign power; and administrative, when it regulates the business which the state has to do...."
Other good examples of public law are tax law and criminal law.
Public law can be distinguished from private law, which regulates the private conduct between individuals, without direct involvement of the government.
Private law and public law can overlap. For example, an unsolicited punch in the nose would constitute a crime for which the government would prosecute under criminal law but for which there would also be a private legal action possible by the injured party under tort law, which is private law (although governments can be held responsible under tort law).
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