Evaluation of institutional aggression within groups in Prisons

This model has received some research support, especially in terms of individual factors such as:

• Age
• Race
• Education level

For example, Harer and Steffenmeier (2006) colleceted data from 58 US prisons and found that black inmates had significantly higher rates of violent behaviour but lower rates of alcohol and drug-related misconduct than white inmates.  

These patterns match racial differences in these behaviours in US society and so support the importation model. 

Evidence from DeLisi et al. (2004) challenges the claim that pre-prison gang membership predicts violence whilst in prison.

They found that inmates, who were involved in street gang before being in prison, were no more likely than other inmates to engage in prison violence.

However, this lack of a correlation between the two, could be explained by the fact that violent gang members tend to be isolated from the general inmate population, therefore they are restricted from violence.

• For example, Fischer (2001) found that isolating known gang members in a special management unit reduced the rate of serious assault by 50%.

There is substantial research evidence to support the claim that peer violence is used to relieve the deprivation that is forced by institutional cultures, such as prisons.

McCorkle et al. (1995) found that overcrowding, lack of privacy and the lack of meaningful activity influenced peer violence.

However, research in this area is not consistent (reliable) in its findings.

Research in psychiatric institutions, for example Nijman et al. (1999), found that increase in personal space failed to decrease the level of violent incidents among patients. 

Jiang and Fischer-Giorlando (2002) found support for both the deprivation and importation models as explanations of prison violence.

They found that the deprivation model was more able to explain violence against prison staff, whereas the importation model was more able to explain violence against other inmates.

The deprivation model is also challenged by research by Poole and Regoli (1983) – they found that the best indicator of violence among juvenile/adolescent offenders was pre-institutional violence regardless of any situational factor in the institution. 

A real-world application of the deprivation model happened at HMP Woodhill in the early 1990’s. David Wilson reasoned that if most violence occurs in environments that are hot, noisy and overcrowded, then this could be avoided by reducing these 3 factors.

Wilson set up two units for violent prisoners that were less claustrophobic and ‘prison-like’ and gave view to outside.

• The typical noise associated with prison life was reduced and masked by music from a local radio station.
• Temperature was lowered so that it was no longer stiflingly hot.

Despite the fact that these changes that nealy removed assaults on prison staff and other inmates, political pressure led to the units changing their rules and developing in a different direction.