He saw criminal behaviour as developing mentally immature in that it is selfish and concerned with immediate gratification- they are impatient and cannot wait for things
-datrol and Holanchock studied Hispanic and African-American offenders in New York and divided them into 6 groups based on criminal history and the nature of the crime
-found all 6 groups were found to be less extravert than non-criminals
-batrol suggested this was because their sample was a different culture group