Tracking Transgressors

In a perfect world, a gun would tell you who used it in a crime … over and over again.

Such is the stuff of science fiction. Gun serial numbers really don’t help (more on that later). But one program and set of sciences is helping to expose repeat offenders and maybe get serious bad actors off the streets.

Take Aways

• 96% of guns recovered in crime are linked to one or more additional cases.
• 83% of guns were used in two or more crimes.
• These statistics may be low due to staffing problems in forensic labs.

Repeat offenders and guns

We know from decades of criminology and some indirect evidence that among the criminal class, there are some super predators who repeatedly misuse guns. Ignore for the moment perps like ATM muggers and liquor store bandits who rarely fire their guns at anyone (instead, the gun is used as “persuasion”). Elsewhere, especially among American street gangs, there is a small set of individuals who are ruthless and shoot people with little regard. Even within street gangs, where fatal violence is common, there are apex predators whom even other gang members fear.

As we have often noted, according to sundry news reports, a gang member in custody for a homicide is the lead suspect in an average of three other homicides. Even though guns trade hands rapidly in Thug World, some perps carry the same gun long enough to use it several times.

That is where a ballistic database exposes this reality and occationally adds multiple charges onto a suspect’s list of new charges.

NIBIN background

The National Integrated Ballistic Information Network (NIBIN) is a government program to capture the markings left on bullets and casings found at crime scenes. The goal is to create a database of evidence about crime guns, with one express purpose being to tie a gun to multiple crimes.

It works basically like this:

• Cops gather spent bullets and cartridge brass from a crime scene or test fire recovered guns.
• Trained lab technicians identify marks left on this evidence which are “largely” unique to the gun used.
• The data is entered into the NIBIN database.
• When evidence is gathered at another crime scene, the marks there are compared to everything in the database, looking for matches (“hits” in NIBIN parlance).
• If matches are found, this is noted; and if a suspect is arrested for any of the crimes the gun was used in, detectives can quickly determine if the suspect was likely the perp in the other crimes.

Please note that this is not the occationally proposed national ballistics fingerprinting database that politicians occationally proffer. This database does not capture ballistic evidence from guns before they are retailed. It is just crime evidence.

The question is whether it does any good. The answer is that the benefits are significant but could be improved.

NIBIN results

Keep in mind that NIBIN is not universal. You might even consider it in startup mode with only 258 labs across 46 states (as of the end of 2021). With some of those cities still ramping up, they may not be fully operational, and in the paper we cover here ¹ from 2017, there appear to be chronic understaffing issues.

That said, in this limited sample (nine agencies) we start to see both the repeat nature of gun crime and the value of the NIBIN system.

Of the 65 cases where the researchers obtained full information and completed interviews with detectives, 63 cases (96%) had at least one additional case that was matched via ballistics (“linked via a ballistics imaging hit to at least one other case”).

That datapoint alone is unsurprisingly staggering. Given that 83% of the primary cases (where the gun or ballistic evidence was recovered) were homicide cases, and 41% of the secondary cases were homicides or assault with deadly weapons cases, we see the apex predator phenomena at play.

click for larger, sharable version

And it gets better (or worse, depending on whether you are data-geeking or horrified about repeat violent offenders). The limited data in this paper shows that the majority of cases where the gun was used in multiple crimes were used in just one other. That said, 27% of the time it was two other cases.

But this is likely an understatement due to a number of factors:

• NIBIN is a relatively new project, launched in 1997. The program itself had to ramp up (funding, recruitment of participating agencies, training agency staff, getting technology acquired/configured, etc.).
• This paper notes very long periods from the recovery of the weapon and/or ballistic evidence to finding a “hit,” an average of 181 days.
• The ramp-up of data in the NIBIN database (too little data, too few hits).

The hits are producing results, but the full promise is not being met. Per the authors of this study:

“Hit reports rarely contribute to identification, arrest, charging, or sentencing of suspects, because of delays in producing hit reports. On average, hit reports were completed 181.4 days after the focal crime. This delay forces investigations to proceed without the benefit of information from ballistics analysis.”

That strong statement shows the current weakness of the system. Supposedly the statistics will improve over time as the database is populated with more forensic data. But the key problem appears to be a case of overload via understaffing. Detectives are not given match data for half a year and thus proceed with their investigations using traditional methods.

click for larger, sharable version

That said, in 17% of cases, NIBIN matches helped identify a suspect, and 3% of cases resulted in an arrest. And these are the cases where no suspect had been identified at the time NIBIN presented a match. In another 17% of cases where a suspect had already been identified, NIBIN matches helped solidify the cases, and the suspects were charged in 3% of those.

Given anecdotal testimony that we at Gun Facts have received from people in government, serial number tracing is producing poor or no results. According to one former state and federal prosecutor in a major metro region, “Not a single violent crime that ever involved a lead developed from just a serial number search.” We hope to validate those claims soon, but for now NIBIN is producing some desirable results and might be on the way to doing much better.

NIBIN the bud

[ED: sorry for his bad pun]

NIBIN shows promise. The question is whether the participating agencies will fund, staff and prioritize NIBIN data to help incarcerate local apex predators. With only 217 participating cities (after we combine duplicate labs and overlapping jurisdictions, such as three for Los Angeles), and some of those being tiny (e.g., Meriden, Connecticut, population 60,000) there is ample room for improvement of this system, which is already producing results.

This article first appeared on Gun Facts. Please make a donation directly to them at https://www.gunfacts.info/donate/