Background: Working dogs have been proven effective in multiple military and law enforcement applications. Similar to their human counterparts, understanding mortality while still in service can help improve treatment of injuries, and improve equipment and training, to potentially reduce deaths. This is a retrospective study to characterize mortality of working dogs used in civilian law enforcement. Methods: Reported causes of death were gathered from two working dog and law enforcement officer memorial websites. Results: Of the 867 civilian law enforcement dogs reported to these memorial websites from 2002 to 2012 with reported causes of death while in service, the deaths of 318 were categorized as traumatic. The leading reported causes of traumatic death or euthanasia include trauma as a result of a vehicle strike, 25.8% (n = 82); heatstroke, 24.8% (n = 79); and penetrating ballistic trauma, 23.0% (n = 73). Conclusion: Although the information gathered was from online sources, this study casts some light on the risks that civilian law enforcement dogs undergo as part of the tasks to which they are assigned. These data underscore the need for a comprehensive database for this specialized population of working dogs to provide the robust, reliable data needed to develop prevention and treatment strategies for this valuable resource.