In: Psychology
There are basically three theories behind each violent crime. These are psychological, sociological and biological. All these theories are overlapped with each others.
Psychological theory considers an individual as a unit. Individual's behaviour is studied and its abnormality is decided by the social consciousness. It considers that mental dysfunctionality and mental disturbances are main cause of criminal activities. In such situations, a person picks an immoral individual as a role model and follows him before commiting a crime.
Sociological view tells that criminal mindset comes from social impact. Group of people can get influenced by certain ideology. Sociologists accept the phenomenon that crime can not be disappeared completely. Harsh punishments can supress sociological aspects of criminal offence.
Biological view tells that criminal aptitude may come from heredity. It also explains that dysfunction of neurotransmitters can lead to criminal behaviour. Mental disorders cause decision impairment in harsh time and can lead to criminal offence.