One explanation of institutional aggression (otherwsie known as IA) are dispositional factors, this means that aggression is determined by a persons pre-existing disposition and personal characteristics that will impact on how aggressive they behave. The theory states that for example, if a large amount of people with aforementioned characteristics are in an institution then it is the norm and IA will occur.
Furthermore, Irwin and Cressey devised a model called the importation model. This model states that a lot of the behaviour shown by these aggressive individuals within the institutions is also shown in wider society, this means that they do not act more aggressively because they are in an institution but they are just importing their aggression to a different location. Cressey, however had gone further in this research to state that in order to understand why IA occurs and to prove what causes it, it becomes necessary to look at the behaviours and traits of inmates outside of the institutions and states that only studying inmates within institutions is the incorrect approach.
Moreover, Mills et al conducted research into this field which supports the idea of pre-existing factors shaping behaviour within prisons. Mills et al found that in a prison within Canada, 202 inmates who were surveyed using the alcohol dependence scale and had a higher level of alcohol depend had also shown to have higher levels of serious institutional misconduct. Thereby the research shows that it is pre-existing factors, such as alcoholism, that determin institutional misconduct. Harer and Steffernmeier studied data from 58 American prisons and had found a correlation between being African American and having a higher level of misconduct within the prison. These pieces of research show a clear correlation between an individuals disposition and their aggression levels within an institution and this implies