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Review of the Roots of Youth Violence: Literature Reviews

The Root Causes of Youth Violence: A Review of Major Theoretical Perspectives

A Report Prepared for the Review of the Roots of Youth Violence

Scot Wortley
Associate Professor, Centre of Criminology, University of Toronto


Randy Seepersad
Andrea Mcalla
Rashmee Singh
Natasha Madon
Carolyn Greene
Nicole Myers
Terrance Roswell


Violent crime involving youth can take many shapes and forms and involve many different types of people. The following cases, for example, represent the many types of violent crime that have taken place in Ontario over the past decade:

These are only a few examples of the types of violent incidents that sometimes take place in our society. The first question that often emerges when faced with such acts of violence is, why? Why did this crime occur? What motivated the offenders to engage in this type of behaviour? Can one theory or explanation account for all of these incidents? Or can violence be caused by multiple factors?

Discovering and documenting the root causes of crime and violence has been a primary objective of crime scholars for over a hundred years. It is widely believed that if we can only identify the cause or causes of criminality, we will be better able to prevent violence in the first place, or at least be in a position to punish, treat, or rehabilitate those identified as violent offenders. A number of academic disciplines – including anthropology, biology, criminology, psychiatry, psychology, social work, and sociology – have developed specific theories to explain the onset and persistence of violent behaviour. Some of these theories focus on how individual propensities – including biological and psychological disorders – increase the probability of violence. At the other end of the spectrum, structural theories propose that variables like poverty, oppression, social inequality and racism must be considered in any explanation of violent behaviour. Still others maintain that the source of violence lies in family dynamics, neighbourhood characteristics or peer socialization processes. It is quite difficult to negotiate and organize the plethora of ideas, hypotheses and empirical findings that mark the study of crime and violence.

The purpose of this report is to briefly outline major theories that have examined the root causes of crime and violence. A full discussion of the many studies and research results associated with each of these theoretical perspectives is well beyond the scope of this document. Indeed, a quick examination of the reference section will reveal that volumes have already been devoted to each of the theories reviewed below. Thus, the purpose of this report is to review the major principles or concepts associated with each theory, examine major research findings that either support or refute these principles, and briefly discuss major policy implications. It should be noted that this report is not concerned with evaluating whether the crime prevention programs or initiatives associated with each theory are effective. Program evaluation, however, is the focus of another report commissioned by the Review of the Roots of Youth Violence.

The discussion below begins with a review of biosocial theories of crime. It includes a discussion of brain chemistry, neurophysiological conditions, genetics and evolutionary factors that account for violent human behaviour. We then turn to a discussion of psychological explanations of crime, including a review of the relationship between personality, intelligence, mental illness and violent behaviour. We then examine rational choice and routine activities theories that hold that all human actions – including violence – are products of rational decision-making at the individual level. We then move on to a discussion of how social conditions – including community disorganization, economic deprivation, social inequality and strain – impact criminality. This section is followed by a review of the social learning and sub-cultural perspectives. These theories maintain that violence is learned through association with deviant role models, including family members and peers. Included in this section is a review of the literature on how the media may impact violent behaviour at both the individual and societal level. The next section reviews the literature on social control and self-control theories of deviance. We then examine theoretical attempts to integrate the major principles of disparate crime causation theories. Finally, the report concludes with a discussion of critical perspectives that greatly expand the definition of violence and point to the role power relations play in the perpetuation of violence in modern societies.


Volume 1. Findings, Analysis and Conclusions

Volume 2. Executive Summary

Volume 3. Community Perspectives Report

Volume 4. Research Papers

Volume 5. Literature Reviews