There are many different theories of criminology that have developed throughout the past 250 years or so, and while some have fallen out of popularity, others are still thought relevant today. The creation of criminology as a field of study can be tracked as far back as the 18th century, when two social theorists, Cesare Beccaria in Italy and Jeremy Bentham in England, each pushed the idea that the punishment should be so severe that the criminal would decide that the pleasure of the criminal act would not be worth the pain of the punishment. This was known as the classical school of criminology.

As recently as 1995, a judge in California sentenced a man to prison for 25 years to life for stealing a slice of pizza. The judge stated that his hands were tied because of the three strikes law, and the law would not allow the judge to look at the specific crime. This example follows the classical school of criminology that was developed over 200 years ago.

During the early 19th century, criminologists started to argue that the classical school of criminology does not differentiate between varying degrees of crimes. These criminologists were known as the positivists. The positivists believed that the punishment should fit the criminal, not the crime.