Criminal law is a branch of public law

Public law comprises constitutional law, administrative law, tax law and criminal law, as well as all procedural law.
Laws concerning relationships between individuals belong to private law .
The relationships public law governs are asymmetric and unequalized.
Government bodies (central or local) can make decisions about the rights of persons.

Criminal procedure is a formalized official activity that authenticates the fact of commission of a crime and authorizes punitive or rehabilitative treatment of the offender .
The first civilizations generally did not distinguish between civil law and criminal law.
The first written codes of law were designed by the Sumerians.

Criminal law, as distinguished from civil law, is a system of laws concerned with crimes and the punishment of individuals who commit crimes.
Thus, where in a civil case two parties dispute their rights, a criminal prosecution involves the government deciding whether to punish an individual for either an act or an omission.