As we discussed in the first article in this series, actions taken during the first 48 hours following a gun crime are of critical importance to an investigation.

There’s no substitute for the fresh opportunity to collect evidence, interview witnesses, and provide community support. What you do in the first 48 hours informs everything that happens after.

But, of course, most investigations don’t end after two days. Those first 48 hours following a gun crime are reactive, responding to an incident that just happened; after that, investigators can switch to a more proactive and strategic approach. The process of identifying the shooters and building a case against them is complex and can continue on for weeks or even months.

Best Practices


An effective and efficient investigation requires following certain best practices, some of which are universal and some of which are agency- and situation-specific. The universal best practices include:

It’s important to remember every department has its own playbook for dealing with different kinds of gun crimes (e.g., multi-victim shootings, gang shooting, engaging with violence interrupters, and so on). An agency can set up automated rules in ShotSpotter Investigate to lay out the proper sequence of actions, establishing their own best practices even before the initial response. Staying organized in this way is essential, especially with so many items happening simultaneously.

NIBIN Prioritization and Tracking


After the CGIC returns information regarding probable or confirmed NIBIN matches, the next step is to track and prioritize leads and assign them for further investigation. Sometimes the CGIC won’t report any matches, and while this may initially be disappointing, it’s important to remember that such investigative groundwork is essential and can often pay off later. For instance, the same weapon used in the gun crime investigation you are working on now could resurface months later during a traffic stop, subsequently providing the investigative momentum needed to finally close a months-old case. It can’t be overstated — doing the proper groundwork of canvassing the crime scene and submitting relevant ballistic evidence to your local CGIC for further analysis can set you up for investigative success, even when you least expect it.

Gathering Historical Data and Deploying Resources

As we mentioned before, many initiatives are happening simultaneously within the context of a gun crime investigation. For instance, as the CGIC processes ballistic evidence to make an assessment about a potential NIBIN hit, investigative teams are actively following up on leads using a system like COPLINK X, as well as implementing proactive efforts to prevent further violence. Such proactive efforts often require a more holistic and historical understanding of gun crime trends in a particular area. To better assess this, crime analysts will produce temporal heat maps that identify where gun violence occurs most often, enabling command staff to determine which communities may need to deploy violence interrupters as well as other critical resources.

Collaborating with Other Agencies


Running down leads and building a case requires connecting disparate pieces of information. That job is helped immeasurably by collaborating with other investigative agencies within the jurisdiction and outside the jurisdiction. To highlight the importance of this, consider the scenario we mentioned earlier, where a gun crime has gone unsolved and then, months later, a weapon recovered during a routine traffic stop is confirmed as a NIBIN hit. Now, imagine the initial gun crime occurred in California and the traffic stop months later occurred in Florida. It is of critical importance that these agencies in California and Florida can collaborate across jurisdictions and share data with one another to prevent this potential offender from committing more crimes.

COPLINK X and ShotSpotter Investigate are two powerful investigative tools that can help law enforcement agencies collaborate with one another more effectively. COPLINK X is a law enforcement search engine that retrieves and consolidates information from police repositories and other data sources. The platform lets investigators use natural language search terms to search 1.3 billion records across more than 40 data sources. Information found might match up with a witness description, address, or another bit of evidence in the current investigation.

The search engine is an extremely helpful tool for investigators to use while assembling their cases in ShotSpotter Investigate, a comprehensive case management platform that provides a digital case folder for organizing, storing, and searching information. The Investigate platform can also incorporate evidence from other sources, such as CCTV video and tips sent from citizens through the community portal.

Ultimately, ShotSpotter Investigate and COPLINK X are both built to enhance collaboration among agencies. The more data available for COPLINK X to sift through, the more information available to store in ShotSpotter Investigate, the more effective an investigation can be.

Feedback to all Applicable Stakeholders


Reporting outcomes and providing feedback to all the personnel involved in an investigation, from the patrol officers who initially recovered evidence, to the investigators who built the case, to the prosecutors who present the case at trial, closes the circle and provides many benefits. For instance, such feedback helps command staff continuously improve on processes, such as assessing caseloads and identifying additional training that may be needed. Additionally, acknowledgment of the critical role that a particular stakeholder played in the investigative process can improve morale, which is especially important at a time when stories about low police morale are more prominent than ever.


The need to effectively investigate gun crimes has never been more pressing, with roughly 21,000 deaths (not counting suicides) and 41,000 injuries occurring every year. It’s important to remember that investigations are part art and part science. The “art” consists of the elements that cannot directly be taught, such as instinct and intuition, while the “science” encompasses the measurable variables, the organized systems, the act of following up on a hypothesis based on significant information obtained from a system like COPLINK X, and so on  Ultimately, merging the art and the science together is critical as investigators look to solve cases in the days, weeks, and months following a gun crime incident.

To learn more about gun crime investigation best practices, watch our webinar on demand.