Criminal law is the body of law that relates to crime. It proscribes conduct perceived as threatening, harmful, or otherwise endangering to the property, health, safety, and moral welfare of people inclusive of one's self. Most criminal law is established by statute, which is to say that the laws are enacted by a legislature. Criminal law includes the punishment and rehabilitation of people who violate such laws.

Criminal law varies according to jurisdiction, and differs from civil law, where emphasis is more on dispute resolution and victim compensation, rather than on punishment or rehabilitation.

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.