Use of force on and by the police: The role of mental disorders

As part of their regular duties, the police can sometimes be required to use force to manage, contain and resolve a situation. At times, they may use lethal force to protect themselves or another person. Previously, the research on these topics has examined not only their prevalence, but also the factors that might influence the occurrence and characteristics of fatal and nonfatal police force. However, research examining the characteristics and the influence that mental disorders might have in these incidents is scarce. The present collection of research examined the frequency and characteristics of mental disorders in fatal and nonfatal incidents of police force in Victoria, Australia. Forty-eight incidents of fatal police force that occurred between 1980 and 2008, and a random sample of 4,267 incidents of nonfatal police force that occurred between 1995 and 2008, were sourced from a dedicated police Use of Force Register, and were subsequently linked with the Law Enforcement Assistance Program (LEAP) and the Redevelopment of Acute and Psychiatric Information Directions (RAPID) databases to examine their criminal and mental health histories. Examinations of fatalities also supplemented this database information with that from the available coronial reports. Findings suggest that mental disorders – mood disorders, anxiety disorders, substance use disorders, personality disorders, psychosis, and schizophrenia – are common and significantly overrepresented in both the incidents of fatal and nonfatal police force. More than half of the fatalities cases (n = 26, 54.2%) and more than third of the nonfatal cases (n = 1621, 38%) had a mental disorder. For instance, a significant overrepresentation of the estimated prevalence of psychosis was found in fatal incidents (OR = 12.51, p < .001, 95%CI [6.65, 23.53]) and in nonfatal incidents (OR = 9.03, p < .001, 95%CI [7.41, 11.01]). Moreover, when examined in further detail, a third of the 45 fatalities (n = 15, 33.3%) met a strictly operationalised criteria for suicide by police; they were found to differ on a number of indicators from those who did not meet the suicide by police criteria, including the presence of mental disorders like schizophrenia and anxiety, of past suicide attempts, and of alcohol use. A small but significant proportion (n = 306, 7.2%) of nonfatal cases were perceived by police to exhibit signs of mental disorder during the incident. Those with diagnosed and perceived mental disorders in nonfatal incidents were significantly more likely to threaten or to use weapons on the police, even after controlling for factors such as substances use, violent behaviour, age and gender (AOR = 1.52, p < .001, 95%CI [1.23, 1.91]; and AOR = 2.08, p < .001, 95%CI [1.53, 2.85], respectively). Of consequence, the findings also suggest that the police were significantly more likely to use or threaten to use weapons on those whom they perceived to be mentally disordered: The police were significantly more likely to use oleoresin capsicum spray on this group than on those whom they did not perceive to be mentally disordered, even after controlling for the effect of important individual factors such as age, gender, violent behaviour, use of force and substances use (AOR = 2.12, p < .001, 95% CI [1.58, 2.85]). The findings borne out of this collection of studies suggest significant implications for the police training and practice, as well as for the broader systems’ interactions and work at this interface. Crucially, systematic changes to both the mental health and the criminal justice systems are required to improve the longer-term justice and mental health outcomes for these people