Irwin and Cressey suggest that prisoners bring their own characteristics and social hierarchy's with them into prison

In the US black inmates are more likely to be involved with interpersonal violence than white inmates due to the coming from poorer communities with higher rates of violent crime, they therefore import cultural norms relating to violence

Pre-prison gang membership appears to be an important determinant of prison violence this could be due to within the gang violence is the norm and gang members bring that attitude when imprisoned

The criminal subculture: Where inmates follow the norms and values of the professional or career criminal, these values include not betraying one another and being trust worthy and reliable among fellow criminals

The convict subculture: Describes inmates that have been raised in the prison system, they seek positions of power, influence and info within the prison system

The Conventional subculture: Tend to be one-time offenders and do not tend to be aggressive while in prison

S: Harer and Steffensmeier analysed data from 58 US prisons, found black inmates had significantly higher levels of violent behaviour but lower rates of alcohol and drug related misconduct than whit inmates, these patterns parallel racial differences in these behaviours in US society and so support the importation model

L: Contradictory evidence by DeLisi who challenges the claim that pre-prison gang membership predicts violence whilst in prison, he found inmates with this were no more likely than other inmate to engage in prison violence, this however may be explained by the fact that violent gang members are sometimes isolated from other prisoners which means that the importation model is still a valid explanation of aggression

Prisoners aggression is a product of the stressful and oppressive conditions of the institution itself

These factors could lead to increased aggression as it is a way to reduce stress, obtain desired resources and gain some control over their lives

5 Deprivations that prisoners may suffer from:

1. Deprivation of liberty
2. Deprivation of autonomy
3. Deprivation of goods and services
4. Deprivation of heterosexual relationships
5. Deprivation of security

S: Research to support, individual level factors can be predictors of aggression independent of the prison environment, but research shows that some situational variables are also highly influential, Cunningham analysed inmate homicides in Texas prisons and found motivations for the behaviour s were linked to some of the deprivations, this increases the validity of situational explanation

L: However research is inconsistent as McCorkle looked at 371 state prisons in the US and found little evidence of a relationship between violence and measure such as over-crowding, he also found that levels of deprivation remain fairly consistent in many institutions and yet violence can erupt suddenly, for seemingly little reason this suggests that explanations are more complex