Murder-suicide in the United States: 1999-2009

This dissertation focused on examining murder-suicide in the United States through descriptive, time-series and spatiotemporal analyses using a self-created and herein verified national database that spanned the years 1999 through 2009. Chapter 2, "Establishment and validation of a national database for murder-suicide in the United States: 1999-2009," describes the methods and sources used in the creation of a national database of murder-suicide. The database was validated using less geographically and/or temporally expansive databases through the use of capture-recapture methods in two ways: the number of events identified in specified space and time was compared and cases were matched using the perpetrator's name. Victim and perpetrator characteristics were then described as compared to previous studies. Chapter 3, "A time-series analysis of murder, suicide and murder-suicide in the United States, 1999-2007" utilized time-series analysis techniques to investigate the impact of time varying covariates on murder, suicide and murder-suicide. Analyses were conducted in the United States at the national level from January 1999 to December 2007. Johansen's multivariable cointegration analysis showed that two-month time lagged murder was positively associated with murder, suicide and murder-suicide. Two-month time lagged suicide was negatively associated with murder, suicide and murder-suicide. Two-month time lagged murder-suicide was not related to any of the three events. Chapter 4, "Spatiotemporal relationships among murder, suicide and murder-suicide in the United States: 1999-2008" examined space, time, and spatiotemporal relationships among murder, suicide and murder-suicide using a spatiotemporal scan statistic from SaTScan^TM. Thirty-five temporal and spatiotemporal clusters of murder, suicide, murder/murder-suicide, suicide/murder-suicide and murder/suicide/murder-suicide were identified. No purely spatial clusters, clusters of murder/suicide without murder-suicide, or purely murder-suicide were identified. The murder-suicide database, that will be made public in 2012, will be a novel source of information for investigators interested in studying murder-suicides with the inclusion of date, place, perpetrator and victim characteristics. Its validation along with the time-series and spatiotemporal analyses provides greater understanding of murder-suicide by itself and compared to murder and suicide.