Abstract
Homicide committed by multiple perpetrators is an understudied area and there has been no research investigating psychiatric differences between multiple and lone perpetrators of homicide. The objective of this study was to explore the demographic, criminological and psychiatric differences of the victims and perpetrators of multiple perpetrator homicides and compare them with the victims and perpetrators of lone perpetrator homicides. A 10-year (1997–2006) consecutive national sample of homicide perpetrators in England and Wales was used in this study. Of the 5806 homicides identified, 1485 were perpetrated by two or more convicted offenders. Convicted perpetrators who engaged in multiple perpetrator homicide were younger and single and less likely to be mentally ill at the time of the offence. It is concluded that supportive services should be provided for young people to reduce the rate of multiple perpetrator homicide.