Criminal laws define crimes and specify punishment for wrongs of a public nature or wrongs committed against the State. Criminal cases are brought by the State or an agency of the government to prosecute crimes, punish wrongdoers, and deter crime.
Substantive law determines the outcome of a case based on the facts.
Procedural law determines the rules to be used to resolve the case. Different categories of crimes result in different punishment and not surprisingly have different procedural rules. More serious crimes have more complicated rules. Punishment for crimes depends on how serious the crime is. Petty offences can usually be handled in one appearance.