New Study: Mental Illness Not Predictive of Crime or Incarceration
A new study challenges the belief that those diagnosed with mental illness are of greater danger to the public-at-large. This issue has become prominent as policy makers seek to develop interventions to address mass shootings.
Israeli researchers believe this approach, which focuses on the relationship between crime and mental illness, is often based on incorrect information. They point out that for a vast majority of psychiatric diagnoses, there is no predictive association with incarceration.
“We do know that there are higher levels of mental illness among prisoners, but this may be a result of incarceration and prison conditions. Our findings show that they are not the predictor of incarceration,” says Prof. Sophie Walsh, of the Department of Criminology at Bar-Ilan University.
The study appears in the journal Psychological Medicine.
For the investigation, researchers examined the relationship between psychiatric diagnoses and future incarceration. The study was based on data of psychiatric interviews performed in a representative sample of the adult population aged 25-34 in the 1980s in Israel.
Professor Bruce Dohrenwend, of Columbia University, and Professor Itzhak Levav, of the University of Haifa, were collaborators on the current study, as well as Professor Gilad Gal, from the Tel-Aviv Yafo Academic College. The research team included members from Tel Aviv University and Sheba Medical Center.
Data on the participants of the cohort study were merged with 30 years of follow-up data from the Israel Prison Service. This unique data set enabled the researchers to see who from the original cohort study of 5,000 was later incarcerated in what may be the first prospective study of its kind.
Study findings showed that diagnoses of substance use and antisocial personality were predictors of future incarceration but that other psychiatric diagnoses (i.e., schizophrenia, affective disorders, anxiety disorders, as well as some other psychiatric disorders) were not independent predictors of incarceration.
In addition, the association between the number and maximal length of incarceration for participants with affective disorders, anxiety disorders, substance abuse, antisocial personality, and ‘other psychiatric diagnoses’ were examined and compared to incarcerated participants with no diagnosed disorder.
Substance abuse was found as a significant risk factor for repeat incarcerations, antisocial personality showed marginal significance, while affective disorders, anxiety disorders, and ‘other psychiatric disorders’ showed no association.
Longer periods of incarceration were associated with substance abuse and, to some extent, with antisocial personality. No significant differences were found for affective disorders, anxiety disorders, and ‘other psychiatric disorders’.
Researchers believe the findings also challenge the myth of ethnic origin and incarceration: among Ashkenazi and Sephardic participants, ethnic origin was not a predictor of incarceration once levels of education were controlled for.
“This study rejects several common stigmas, such as ethnic origin and psychiatric diagnoses, as a predictor of incarceration,” says Walsh.
Researchers are hopefully that the findings will encourage treatment for substance abuse and antisocial personalities and increase awareness of mental illness in prisons.
Source: Bar-Ilan University/EurekAlert