Investigating serial murders requires both a proactive and a reactive approach. Proactive methods are generally designed to prevent future crimes from occurring by taking action now on known variables. Reactive approaches include tactics and techniques used when police respond to crimes that have already occurred. Both proactive and reactive approaches are needed when addressing the problem of serial murder. Proactive methods used for serial murder are similar to tactics used for broader crime prevention, such as increased police visibility and presence throughout the neighborhood. Big data helps police improve the efficacy of proactive methods, by helping law enforcement identify patterns of the serial murderer’s behavior or patterns of victimization. When specific geographic areas of concern have been identified, patrols can then target those areas, helping the police department allocate resources wisely while also preventing crime using data-driven methods. To be as effective as possible in preventing future crimes, the police patrols need to be data-driven but also “highly visible,” (“Proactive Policing,” 2015, p. 1). Databases can also help police develop more effective communications strategies, such as having strategies in place to warn residents in vulnerable areas and offer evacuation options.

Another crucial component of proactive policing is akin to community policing, whereby officers build relationships with members of the community systematically. Relationships are cultivated...

As trust and respect between officers and the community builds, residents and business owners will be more likely to report suspicious behavior, offering tips and direct assistance to police when needed. The police can also leverage relationships with community members to perform more strategic and effective surveillance. For example, if police want to install more CCTV, the cooperation and assent of business owners may be required. If resources are spread thin in the department, members of the community might also cooperate and collaborate with police on the monitoring of CCTV or participate in neighborhood watch programs.
Proactive policing often interfaces, rather than interferes, with reactive policing. For instance, some of the same proactive methods used to prevent future crimes can be used for more effective responses to a new incident. Increased visible patrol units also allows officers to reduce response times and offer safer and less intrusive reactions to malicious behavior. Likewise, proactive methods like profiling software can help patrol units to make positive identifications and prevent wrongful arrests. In fact, behavioral analysis is both a proactive and a reactive measure that has been proven effective in serial murder investigations in particular (Hall, n.d.). Also, routine patrol procedures are both proactive and reactive (Department of Justice, 2015).

Specifically reactive methods include…