An idea to achieve social control. Your conscience guides you to follow laws and rules due to experiencing feelings of guilt, anxiety or worry from within.
Internalisation of social rules
When a person agrees and believe in social norms and therefore internalises them and follows them. A societal norm is to not commit crime; therefore, most people internalise this and behave accordingly.
Tradition
Conforming to social norms and rules through a person's traditions and upbringing teaching you and re-enforcing you to not break the law