Microstamping and ballistics identification can reduce gun violence by improving the solve rate of gun-related crimes.
Marking fired cartridges with identifying information through microstamping and ballistics identification provides an avenue for law enforcement to pursue those who commit gun crimes. By connecting evidence found at the scene of a shooting, like a spent ammunition cartridge, to the gun that was used—and by extension the original purchaser—law enforcement can better investigate gun crimes and hold violent offenders accountable.
Too many gun crimes go unsolved, a fact that contributes to higher rates of gun violence in the United States. Where gun crimes, especially murder, do not result in criminal charges, people are more prone to take the law into their own hands—often with tragic and deadly results. As Jill Leovy vividly depicts in her 2015 book, Ghettoside, this sort of vigilante justice exacerbates the cycle of retaliatory violence. 1 It’s no coincidence that in a city like Chicago, where the homicide solve rate is as low as 21%, gun violence rates are astronomical. 2 By way of comparison, the Murder Accountability Project estimates that the national homicide clearance rate in 2015 was 61.5%. 3 In many cities like Chicago, there is much room for improvement. Ballistic imaging and microstamping technologies have the potential to reduce gun violence by improving the solve rate of gun-related crimes.
One reason gun crimes are so difficult to solve is that very little evidence is usually left behind at the scene, with the exception of spent cartridge cases that are expelled when a gun is fired. Not surprisingly, cartridge cases are much more likely to be recovered at the scene of a shooting than the gun itself. 4 Both ballistic identification and microstamping systems help law enforcement officials investigate gun crimes because they can accurately identify the gun from which a cartridge case was fired. 5 By linking the cartridge cases recovered at crime scenes to the gun that fired them, ballistic identification and microstamping technologies make it easier to solve gun crimes.
With this information, investigators can create important leads that help to crack cases, including identifying the original purchaser of the firearm, or linking a firearm to multiple crimes that may involve the same suspect. For example, on July 10, 2007, a gunman shot and killed three people in their apartment in North Charleston, South Carolina. Investigators used an automated ballistics identification system to determine that the gun used had also been fired several months previously outside a nearby bar. The bouncer at the bar was then able to identify the person who had fired the gun at that time. Corroborating evidence confirmed that the person was guilty of the triple murder, and he was subsequently convicted. Without the assistance of ballistic identification, this crime would have been much more difficult—if not impossible—to solve. 6
Ballistic identification is based on the fact that all firearms leave unique markings on the cartridge cases they expel when fired, leaving behind a sort of fingerprint that allows law enforcement experts to link cartridge cases to the specific gun that fired them. 7
In the early days of ballistic identification, this process was conducted by individual technicians and was extremely time-consuming because of the sheer volume of images that needed to be manually reviewed. However, in the mid-1990s, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) pioneered the concept of using automated ballistic imaging and computer comparison equipment to analyze crime gun evidence, making the identification process much faster and more efficient. 8 ATF’s National Integrated Ballistic Information Network (NIBIN) was rolled out in June 2000 and currently provides Integrated Ballistic Identification System (IBIS) equipment to approximately 150 state and local law enforcement agencies nationwide. 9 The mission statement of NIBIN is “To identify, target, and prosecute shooters and their sources of crime guns.” 10
IBIS equipment is used to compare images of marked cartridge cases found at crime scenes to ballistic images previously entered into the NIBIN database. When a “match” (or “hit”) is found, firearms examiners are able to conclude that the same gun was used in both crimes. Recovered crime guns are also test-fired and their ballistic images entered into the system, allowing law enforcement to determine whether those guns were used in other crimes. A 2004 study of the Boston Police Department showed that the use of NIBIN “was associated with a more than sixfold increase in the monthly number of ballistics matches,” and that the technology allowed law enforcement to make matches that “would not have been possible using traditional ballistics methods.” 11
A 2005 audit by the Office of the Inspector General (OIG) confirmed that by “minimizing the amount of non-matching evidence that firearms examiners must inspect to identify a hit, the NIBIN program enables law enforcement agencies to discover links between crimes more quickly, and also to discover links that would not have been possible to find without the technology.” 12 Indeed, ATF reports that the NIBIN system as a whole has generated more than 75,000 matches to crime guns since it was introduced. 13
However, these results do not automatically translate into improved crime solving capacity. The OIG report and more recent evaluations have found that, despite its crime solving potential, NIBIN is used very irregularly in the various jurisdictions where it has been deployed, leading to vastly different outcomes in terms of its usefulness to crime investigators. In 11 states, for example, there is no NIBIN terminal at all, and 19 states have only one or two terminals. 14
Even where terminals are in place, poor processes and lack of resources have led to crippling backlogs. A 2013 report to the National Institute of Justice (NIJ), for example, found that due to long processing delays, most of the violent crime cases analyzed for the study “were either [already] solved or slipping into the cold case file by the time the NIBIN hit report arrived.” 15 For a NIBIN match to be useful, criminal investigators must generally receive the information within a few days or weeks, at most. Yet the NIJ report found that at “most selected NIBIN sites, investigators are unlikely to receive a NIBIN hit report within a few weeks of a crime.” 16 At some sites, backlogs were so severe that the sites were “incapable” of quickly processing data that could be used to solve gun-related cases. 17
However, certain sites were found to be models of effective and strategic NIBIN use, and ATF is working to promote replication of these models in other areas. Kansas City, for example, uses NIBIN in conjunction with a sophisticated social network analyses as part of focused deterrence strategies that are designed to reduce gang and gun-related offences. 18
A new national model may come from Denver, which created a Crime Gun Intelligence Center (CGIC) in 2013 in order to coordinate a multi-agency approach to processing NIBIN information and investigating gun crimes more effectively. 19 According to Greg LaBerge, the director of the Denver Police Department’s Forensics and Evidence Division, in less than two years, CGIC was credited for assisting with the arrest of 25 repeat shooters connected to 40 different incidents. 20 As just one example, in January 2015, shell casings from multiple shootings were quickly entered into NIBIN and linked to a single 9mm firearm. Denver’s CGIC then used this lead to identify and arrest the shooter, who ultimately pled guilty and was taken off the streets. 21
CGIC is promising enough that the Bureau of Justice Assistance is providing more than $5.6 million for cities like the District of Columbia, Milwaukee, and Los Angeles to replicate the strategy. 22
For all jurisdictions with NIBIN access, ATF recommends the following best practices in order to improve efficacy: 1) comprehensive collection and entry of evidence; 2) fast turnaround of NIBIN-generated leads; 3) investigative follow-up and prosecution of gun offenders; 4) feedback from law enforcement and community members. 23 Jurisdictions looking to improve the efficiency of their NIBIN programs can find resources and training from ATF at the following website: www.atf.gov/firearms/nibin-resources.
A number of evaluations of NIBIN and the CGIC strategy are expected soon. It’s important that researchers continue to evaluate the effectiveness of these strategies, especially given that NIBIN is not necessarily cheap. Its budget is set to grow to $36 million in fiscal year 2017 from $13 million in 2013. 24 If results cannot be demonstrated at this level of funding, other evidence-based practices, such as Group Violence Intervention (also known as “focused deterrence”), may provide a more cost-effective investment of federal dollars.
Jurisdictions with high levels of gun violence should consider refining NIBIN practices so that leads can actually be used by investigators. A 2016 study of reforms made by the Stockton Police Department in California confirms that strategic changes to personnel, technology, and processes can lead to large improvements in NIBIN program productivity in a relatively short period of time. 25 This improvement can be further facilitated by the implementation of Crime Gun Intelligence Centers as a way to focus law enforcement resources on identifying and arresting the most dangerous shooters. This approach is recommended and supported by the Police Executive Research Forum. 26
Microstamping is a newer technology that utilizes lasers to make precise, microscopic engravings on the internal mechanisms of a semiautomatic pistol, such as the breech face and firing pin. When the gun is fired, a unique alpha-numeric code identifying the gun’s make, model, and serial number is stamped on to the cartridge case. 27 Instead of having to compare images of spent cartridge cases as with ballistic imaging, with microstamping technology identifying information—including a serial number—is automatically imprinted directly on to every single cartridge case that is expelled from a fired handgun.
Microstamping potentially gives law enforcement a significant investigative tool to solve gun-related crimes. 28 When a cartridge case has been engraved with a code through microstamping, the code allows law enforcement to connect the cartridge case directly to the gun that fired it, much like the license plate on a vehicle allows law enforcement to identify the vehicle’s make, model, and VIN number. Studies have shown that semi-automatic pistols equipped with microstamping technology produce a significant amount of ballistic evidence that would not be produced if the pistol did not include the technology. 29
In addition to assisting in the investigation and prosecution of gun crimes, this cutting-edge technology will help deter gun trafficking. Traffickers often purchase guns intending to transfer them to someone else illegally. A trafficker who purchases a gun for this purpose would be on notice that spent cartridge cases could be used to trace the gun directly back to him or her if the gun is later used in the commission of a crime.
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In 2010, the American Bar Association (ABA) recommended that federal, state, and territorial governments enact microstamping laws that would enable law enforcement officers to identify the weapon used in a crime and the purchaser of that firearm. 30 The ABA concluded that “Microstamping technology will be a material aid to law enforcement in the effort to solve crimes committed by use of guns.” 31
Similarly, the International Association of Chiefs of Police (IACP) issued a resolution in 2008 supporting the use of microstamping technology in criminal investigations. The IACP specifically identified microstamping as an inexpensive yet effective way to mark and identify cartridge cases. 32 The IACP concluded that this technology would help law enforcement to identify the purchaser of a weapon used in a crime, “providing leads that would allow for substantial evidentiary information that will help identify, apprehend and arrest criminals.” 33
California was the first state to adopt a law requiring handguns to be equipped with microstamping technology, as described below. That law went into effect on May 17, 2013. 34 However, the law is the subject of ongoing litigation in the California court system, where the gun lobby is arguing that the microstamping requirement is “impossible” to comply with.
Ammunition serialization is another law enforcement tool that can assist in solving more gun-related crimes. For more information about ammunition serialization, see our summary on Ammunition Regulations.
For information about how law enforcement may identify the owner or purchaser of a firearm after determining that the firearm was used in a shooting, see our summary on Maintaining Records and Reporting Gun Sales.
The Firearms Owners’ Protection Act of 1986 prohibits the establishment of any system of registration of firearms, firearm owners, or firearms transactions. 35 The Department of Justice takes the position that this law prohibits “directly linking ballistic images through a centralized computer database” such as NIBIN. 36 In addition, language included in the ATF’s annual appropriations bill requires that ballistic images of bullets and cartridge casings from newly manufactured, imported, or sold firearms are not to be available in or connected to NIBIN. 37
In order to ensure that these provisions are not violated, ATF requires NIBIN users to sign an MOU agreeing not to enter such data. The Office of the Inspector General audited the NIBIN system in 2005 and found “no evidence that prohibited data had been entered into NIBIN.” 38
California, New Jersey, New York, and the District of Columbia have adopted microstamping requirements for some or all firearms, although none have yet gone into effect. Connecticut operates a statewide firearms evidence databank that stores ballistic information on handguns recovered or used by police. Maryland recently repealed a law that created a statewide ballistics imaging database for new handguns sold in state. A similar requirement in New York was also repealed in 2012 prior to the re-enactment of a new microstamping law in 2022. Cost and efficiency issues related to these programs were cited as the reason for the repeal of these laws.
With legislation passed in 2007, California became the first state to require the use of handgun microstamping, an innovative technology that enables law enforcement to match cartridge cases found at a crime scene to the gun’s owner. On October 13, 2007, Governor Arnold Schwarzenegger signed into law the Crime Gun Identification Act, which requires all new models of semiautomatic pistols manufactured or sold in California to be designed and equipped with microstamping technology. The law required the California Department of Justice (DOJ) to certify when microstamping technology was available to more than one manufacturer unencumbered by patent restrictions. DOJ made this certification in May 2013. 39 However, the law is currently tied up in pending litigation before California courts, where the gun lobby is arguing that the microstamping requirement is “impossible” to comply with.
In 2023, California passed legislation expanding the microstamping requirement. Beginning January 1, 2028, licensed firearms dealers will be prohibited from selling any semiautomatic handgun, unless it has been verified as microstamping-enabled, if the California DOJ has determined that microstamping is available. 40 The law also prohibits anyone from modifying a microstamping-enabled handgun with the intent to prevent the production of a microstamp. 41
In 2022, New Jersey enacted a comprehensive microstamping law that requires gun dealers to sell at least one model of a microstamping-enabled firearm once a commercially viable model is certified by the state attorney general and included in a roster of microstamping-enabled firearms. 42
In 2022, New York enacted a microstamping law that requires gun dealers who sell handguns to sell only handgungs that are microstamping-enabled once a the technilogical viability of microstamping is certified by the Division of State Police. 43
Since January 1, 2018, the District of Columbia prohibits any licensed dealer from selling or offering for sale any semiautomatic pistol manufactured on or after January 1, 2018 that is not “microstamp-ready.” “Microstamp-ready” means a semiautomatic pistol that is manufactured to produce a unique alpha-numeric or geometric code on at least two locations on each expended cartridge case that identifies the make, model, and serial number of the pistol. Beginning January 1, 2018, a semiautomatic pistol must be microstamp-ready if it is:
A semiautomatic pistol manufactured after January 1, 2018, that is not microstamp-ready and that was acquired outside of the District by a person who was not a District resident at the time but who subsequently moved to the District is allowed, and may be sold, transferred, or given away, but only through a licensed firearms dealer.
In addition, beginning January 1, 2018, a manufacturer transferring a pistol to a firearms dealer for sale in the District will be required to certify whether the pistol was manufactured on or after January 1, 2018, and, if it was, that:
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Connecticut requires the Division of Scientific Services (“Division”) of the Connecticut Department of Emergency Services and Public Protection to establish a firearms evidence databank. The databank is a computer-based system that stores images of fired components of ammunition in a manner suitable for retrieval and comparison to images of other fired components of ammunition stored in the databank. Handguns recovered by police through a criminal investigation may be submitted to the Division laboratory for test firing and collection of fired components of ammunition. Police departments are also required to submit all handguns issued to employees for test firing and collect fired components of ammunition from the test fire. 45
It is the state policy of Delaware for its law-enforcement agencies to employ electronic technology and inter-jurisdictional information and analysis sharing programs to deter and solve gun crimes. 46 As part of this policy, law enforcement agencies that recover firearms or spent shell casings at the scene of a crime must submit ballistics information, as soon as possible, to NIBIN. 47 This will help determine whether the firearm in question is related to a prior crime or to an individual who may be associated with prior criminal activity. In addition, the Department of Safety and Homeland Security, in cooperation with the Department of Justice, must develop and promulgate a statewide standard protocol for the recovery and forensic processing of firearms and firearm-related evidence where the gun was used for any unlawful purpose or recovered from the scene of a crime. 48
Maryland repealed its ballistic identification requirements in 2015. 49 Between 2000 and 2015 Maryland required manufacturers to test-fire all handguns shipped into the state and provide a spent cartridge case to the purchasing firearms dealer. After sale of a gun, the dealer was required to forward the case to the state police, who would then enter its unique markings in a database for possible use in future criminal investigations. However, this statewide system proved inefficient and was eventually scrapped due to cost concerns. 50
In 2019, Nevada enacted a law that requires law enforcement agencies in counties with populations of 100,000 people or more to submit recovered semiautomatic handguns used or suspected of being used in crimes, and their shell casings, to a forensic laboratory for testing. The resulting data must be entered into NIBIN. 51
In New Jersey, when a law enforcement agency seizes or recovers a firearm that was abandoned or discarded, unlawfully possessed, used for any unlawful purpose, recovered from the scene of a crime, or is reasonably believed to have been used or associated with the commission of a crime, the agency must arrange for the firearm to be test-fired and the ballistics information must be submitted to the National Integrated Ballistics Identification Network (NIBIN). 52 Whenever a law enforcement agency recovers any spent shell casing at a crime scene or has reason to believe that the recovered spent shell casing is related to or associated with the commission of a crime or the unlawful discharge of a firearm, the agency must submit the ballistics information to NIBIN. 53
Beginning December 3, 2022, New York requires a state or local law enforcement agency that seizes or recovers a gun that was unlawfully possessed, recovered from the scene of a crime, or is reasonably believed to have been used or associated with the commission of a crime, or is recovered by the agency as an abandoned or discarded gun, to determine if the gun is suitable for test-firing and of a type that is eligible for national integrated ballistic information network data entry. If so, it must be test-fired as soon as practicable, and the results must be submitted forthwith to the national integrated ballistic information network to determine whether the gun is associated or related to a crime, criminal event, or any individual associated or related to a crime or criminal event or reasonably believed to be associated or related to a crime or criminal event. 54
Whenever a state or local law enforcement agency recovers any ammunition cartridge case that is of a type that is eligible for national integrated ballistic information network data entry and correlation at a crime scene, or has reason to believe that such recovered ammunition cartridge case is related to or associated with the commission of a crime or the unlawful discharge of a gun, the agency shall, as soon as practicable, arrange for the ballistics information to be submitted to the national integrated ballistic information network. 55
The features listed below are intended to provide a framework from which policy options may be debated. A jurisdiction considering new legislation should consult with counsel.
