The National Incident-Based Reporting System February 1, 2021
(NIBRS): Benefits and Issues
Emily J. Hanson
Since 1930, the Federal Bureau of Investigation’s (FBI’s) Uniform Crime Reporting (UCR)
Analyst in Social Policy
program has collected and published nationwide crime statistics. State and local law enforcement

agencies, as well as federal agencies, voluntarily submit data on reported crimes that occur in
their jurisdictions to UCR. UCR then compiles and publishes the data, and provides datasets and

some trend analyses in a standardized format that legislators, researchers, and law enforcement
agencies can access to better understand and address crime in the United States.
The UCR program previously collected crime data from federal, state, local, and tribal law enforcement through the older
Summary Reporting System (SRS) and the more recently introduced National Incident-Based Reporting System (NIBRS).
On January 1, 2021, the FBI retired the SRS program and will only collect data using NIBRS. This report provides
background on the development and adoption of NIBRS as well as details about both the benefits and potential issues related
to this change.
The shift to NIBRS is intended to yield many benefits including improved reliability, accuracy, accessibility, and timeliness
of national crime data. NIBRS expanded the number of crimes for which data are collected from 30 to 84 different offenses.
NIBRS also includes details about these crimes that were not previously measured in SRS. For example, NIBRS allows
police to report, when applicable, the relationship between the victim and offender, the types of property damaged or drugs
seized, and bias motivation (e.g., race, religion, sexual orientation, disability, gender, gender identity). Perhaps the most
significant change in NIBRS is the elimination of the hierarchy rule that applied in SRS. The hierarchy rule required police to
report only the most serious offense if an incident included several crimes. For example, if a n aggravated assault and a
burglary occurred within a single incident, only the assault was reported to the FBI via SRS. In contrast, NIBRS allows law
enforcement to report up to 10 co-occurring offenses per single incident.
There are concerns about how this shift may affect crime rates, agency participation rates, and access to federal grants. The
elimination of the hierarchy rule has raised concerns that counting all crimes that occurred during an incident will make it
seem as if crime has increased; however, these concerns may not be warranted in many situations. Across two studies that
examined the effect of shifting to NIBRS, neither found significant changes in reported crime rates, though data do indicate
that NIBRS may have more of an influence on crime rates in smaller or lower-crime jurisdictions. Another concern is that
fewer agencies will participate in NIBRS compared to SRS, and as a result, data quality will suffer. Lower agency
participation rates can have consequences for understanding crime both in the present and over time. Policymakers might
consider whether to direct the FBI or the Bureau of Justice Statistics (BJS) to examine data gaps and determine where it may
be advisable to target resources to increase NIBRS participation.
An additional concern relates to federal grants that base funding on crime data reported to UCR. Several federal grants, most
notably the Edward Byrne Memorial Justice Assistance Grants (JAG) program, use UCR crime data to calculate allocations
for state, local, and tribal governments. Any state that previously submitted data to UCR via SRS can no longer use this
format as of January 2021. As a result, jurisdictions that struggle with the shift to NIBRS may lose out on the funds
determined by the reported number of crimes.

Congressional Research Service

link to page 13 The National Incident-Based Reporting System (NIBRS): Benefits and Issues

Introduction
Since 1930, the Federal Bureau of Investigation’s (FBI’s) Uniform Crime Reporting (UCR)
program has collected nationwide crime statistics.1 Federal, state, local, and tribal law
enforcement agencies voluntarily submit data about reported crimes that occur in their
jurisdictions to UCR. UCR then compiles and publishes the data, and provides datasets and some
trend analyses in a standardized format that legislators, researchers, and law enforcement
agencies can access to better understand and address crime in the United States.
The UCR program previously collected crime data from federal, state, local, and tribal law
enforcement through the older Summary Reporting System (SRS) and the more recently
introduced National Incident-Based Reporting System (NIBRS).
On January 1, 2021, the FBI retired the SRS program and wil only collect these data in NIBRS.2
This retirement does not mean that past SRS data wil not be available for use, but rather that
going forward, data wil not be collected via SRS.
The SRS program began as a paper-based system in the 1930s, and although it advanced over
time to incorporate more crimes and electronic submissions, its scope remained limited.3 SRS
captured data in two categories of crimes, labeled Part I and Part II offenses.4 There were 10 Part
I offenses: 4 violent offenses (criminal homicide, rape, robbery, and aggravated assault), 4
property offenses (burglary, larceny-theft, motor vehicle theft, and arson),5 and 2 human
trafficking offenses. Data were collected on the number of Part I offenses reported to police as
wel as the number of arrests. There were 20 Part II crimes (e.g., fraud, gambling, drunkenness,
vandalism) for which the FBI only collected arrest data.6
NIBRS was developed by the FBI to address several shortcomings of SRS. First, NIBRS
expanded the number of crimes for which data are collected. NIBRS groups crimes into two
categories labeled Group A and Group B offenses. Group A includes 71 offenses in 28 categories
and Group B includes 13 offenses (for a complete list of crimes captured in both the SRS and
NIBRS programs, see Appendix).7 NIBRS also includes details about these crimes that were not
previously measured in SRS. For example, NIBRS al ows law enforcement agencies to report the
relationship between the victim and offender, the types of property damaged or drugs seized, and
bias motivation (e.g., race, religion, sexual orientation, disability, gender, gender identity).8

1 U.S. Department of Justice, Federal Bureau of Investigation, SRS to NBIRS, https://www.fbi.gov/services/cjis/cjis-
link/srs-to-nibrs-the-path-to-better-ucr-data (hereinafter, “ SRS to NIBRS”).
2 SRS to NIBRS.
3 SRS to NIBRS.
4 U.S. Department of Justice, Federal Bureau of Investigation, Criminal Justice Information Services Division,
Uniform Crime Reporting Program, Sum m ary Reporting System User Manual, pp. 20-22 (hereinafter, “ SRS User
Manual”).
5 U.S. Department of Justice, Federal Bureau of Investigation, Crime in the U.S. 2019, https://ucr.fbi.gov/crime-in-the-
u.s/2019/crime-in-the-u.s.-2019.
6 Law enforcement agencies were able to report runaways in SRS as a Part II offense, but as of 2009 this was no longer
required. T he FBI does not report data on runaway offenses, and as a result runaway is not counted as one of the
official Part II offenses.
7 U.S. Department of Justice, Federal Bureau of Investigation, NIBRS Quick Facts, https://www.fbi.gov/file-repository/
ucr/nibrs-quick-facts.pdf/view, pp. 1-2 (hereinafter, “ NIBRS Quick Facts”).
8 U.S. Department of Justice, Federal Bureau of Investigation, Criminal Justice Information Services Division, Uniform
Crime Reporting Program, 2019.2.1 National Incident-Based Reporting System User Manual, September 2020, pp. 78-
Congressional Research Service

1

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

Perhaps the most significant change in NIBRS is the elimination of the hierarchy rule that applied
to SRS.9 The hierarchy rule required law enforcement agencies to report only the most serious
offense if an incident included several crimes.10 For example, if an aggravated assault and a
burglary occurred within a single incident, only the assault was reported to the FBI via SRS. In
contrast, NIBRS al ows law enforcement to report up to 10 co-occurring offenses per single
incident.11 As a result, NIBRS data can be a more accurate representation of the incidences of
various types of crimes committed in the United States.12
NIBRS was made available to law enforcement agencies beginning in the late 1980s.13 During the
ensuing years, agencies could report their crime data in either the SRS or NIBRS formats. In
2016, the FBI announced that it would retire the SRS program in January 2021.14 Now that SRS
is retired, law enforcement agencies are not able to report data to the FBI in that format. The FBI
estimated that it would take law enforcement agencies between one to two years to convert their
data reporting systems.15 To aid agencies in meeting the January 2021 deadline, federal grants like
the Edward Byrne Memorial Justice Assistance Grants (JAG) al ow grantees to use funds to help
cover the cost of conversion. For example, from FY2018 to FY2020 JAG recipients that were not
certified NIBRS compliant were required to use 3% of any JAG award toward that purpose.16
The most recent data released by the FBI indicated that in 2019, al 50 states, as wel as
Washington, DC, and Puerto Rico, had law enforcement agencies that reported data to UCR in
either SRS, NIBRS, or both formats.17 In that year, 80% of active law enforcement agencies
reported 12 months of crime data to UCR and 89% of active law enforcement agencies reported
at least one month of data.18 These data indicate that although there was not full participation, a
majority of active agencies did report crime data to the FBI. Seven states and Puerto Rico did not
participate in NIBRS in 2019.19 However, among Washington, DC, and the 43 states that did

79 (hereinafter, “ NIBRS User Manual”).
9 NIBRS User Manual, p. 150.
10 SRS User Manual, pp. 23-24.
11 U.S. Department of Justice, Federal Bureau of Investigation, 30 Questions and Answers about NIBRS Transition,
https://www.fbi.gov/file-repository/ucr/30-faqs-about -nibrs-transition-oct-2018.pdf/view, p. 8 (hereinafter, “ 30
Questions”).
12 30 Questions, p. 9.
13 See CRS Report RL34309, How Crime in the United States Is Measured, by Nathan James and Logan Rishard
Council, pp. 9-10.
14 U.S. Department of Justice, Federal Bureau of Investigation, The FBI’s Transition to a National Incident-Based
Reporting System (NIBRS)-Only Data Collection, https://www.bjs.gov/content/pub/pdf/nibrs.pdf
15 30 Questions, p. 13.
16 For more information on the JAG program, see CRS In Focus IF10691, The Edward Byrne Memorial Justice
Assistance Grant (JAG) Program , by Nathan James.
17 U.S. Department of Justice, Federal Bureau of Investigation, Uniform Crime Reporting Program Participation Data,
http://s3-us-gov-west-1.amazonaws.com/cg-d4b776d0-d898-4153-90c8-8336f86bdfec/
ucr_participation_1960_2019.csv (hereinafter, “ UCR program participation data”). The FBI’s Crime Data Explorer
webpage states: “UCR Program participation data provides information about agencies that report data, regardless of
format (summary or incident -based data), to the UCR program. T hese data help clarify the percentage of the population
covered by reported data.” T here are data and statistics reported elsewhere by the FBI that do not completely align with
this dataset; however, given that this is the official dataset the FBI provides for the purposes of understanding UCR
participation, CRS proceeded with these data.
18 Email correspondence with Federal Bureau of Investigation, Global Law Enforcement Support Section, January 14,
2021; and UCR program participation data.
19 Non-participating states/territories were Alaska, California, Florida, Puerto Rico, New Jersey, Nevada, New York,
and Wyoming. Both New York and California have received federal aid to develop state-specific programs that will be
Congressional Research Service

2

link to page 13 The National Incident-Based Reporting System (NIBRS): Benefits and Issues

participate in NIBRS, at least 27, or 63%, had half or more of their UCR participating agencies
using NIBRS. Among these 27 higher participation states, al but three had law enforcement
agencies that were reporting to NIBRS that covered half or more of the states’ populations and 18
covered more than 90% of the population.20
The National Crime Statistics Exchange (NCS-X)
In 2013, the Bureau of Justice Statistics (BJS) and FBI partnered to launch the NCS-X, “a program designed to
generate national y-representative incident-based data on crimes reported to law enforcement agencies.”21
Because the United States has yet to achieve ful participation in UCR or NIBRS, crime rates and statistics are
bound by the available data. This is not an uncommon issue and statisticians frequently use data from a subset, or
sample, of a population to generate estimates about the ful population.22 The underlying idea is that as long as a
sample shares the attributes of the whole population, it can be used to estimate the characteristics of the whole.23
For example, if 50% of law enforcement agencies have fewer than 25 officers then a sample of law enforcement
agencies should contain, to the degree possible, approximately the same proportion. Similarly, whatever
proportion of agencies serve urban or rural communities, the sample should match these characteristics. Statistics
calculated using a sample of a population are referred to as estimates. The NCS-X is to add incident-based crime
data from a stratified random sample of 400 additional law enforcement agencies to those reporting to NIBRS to
attempt to fil in the gaps and generate national crime estimates.24 As an additional benefit, agencies that participate
in NCS-X are to receive technical assistance and funding that may aid them in shifting to NIBRS.25 Estimates such
as these are subject to error arising from the sample (i.e., differences between the obtained sample value and true
population value) and non-sampling errors such as incorrect or dishonest reports.26
This report discusses the expected benefits of the NIBRS program as wel as possible sources for
concern, particularly about the potential consequences of lower participation from law
enforcement agencies.
Benefits of NIBRS
According to the FBI, the shift to NIBRS wil improve the “reliability, accuracy, accessibility, and
timeliness” of crime data in the United States.27 For example, NIBRS captures a larger variety of
crimes than did SRS (see Appendix).28 NIBRS also collects more details about each incident that

NIBRS compliant. California has the California Incident -Based Reporting System (CIBRS) and New York has the New
York State’s Incident-Based System (NYSIBR). For more information, see https://www.bjs.gov/content/nibrs2.cfm.
20 In states where less than half of the law enforcement agencies reported to NIBRS in 2019, the participating agencies
covered, on average, 22% of the population.
21 U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, “National Crime Statistics
Exchange Powering the T ransition to NIBRS,” https://www.bjs.gov/content/ncsx.cfm (hereinafter, “Powering the
T ransition”).
22 Christian Heumann and Michael Schomaker Shalabh, Introduction to Statistics and Data Analysis (Springer
International Publishing Switzerland, 2016), p. 181 (hereinafter, “Introduction to Statistics and Data Analysis”).
23 Introduction to Statistics and Data Analysis, p. 181.
24 For more detailed information on the sampling technique employed by NCS-X see, https://www.bjs.gov/content/
ncsx.cfm.
25 Powering the T ransition.
26 For more information see CRS Report RL34309, How Crime in the United States Is Measured, by Nathan James and
Logan Rishard Council, pp. 26-27.
27 U.S. Department of Justice, Federal Bureau of Investigation, Are You Ready? The Countdown to NIBRS,
https://www.fbi.gov/services/cjis/cjis-link/are-you-ready-the-countdown-to-nibrs (hereinafter “ Are You Ready?”).
28 Many resources about the benefits of NIBRS cite the expansion of the definition of rape to include both male and
female victims. NIBRS included this expanded definition from its inception, though in 2013 SRS also expanded its
definition of rape to the following: “ Penetration, no matter how slight , of the vagina or anus with any body part or
Congressional Research Service

3

link to page 9 link to page 9 The National Incident-Based Reporting System (NIBRS): Benefits and Issues

were not previously included in SRS (e.g., the time of day and the relationship between the victim
and offender).29 Further, NIBRS al ows users to distinguish between completed and attempted
crimes.30 NIBRS also expands the hotel rule to include storage facilities.31 The hotel rule states,
“If a number of units under a single manager are the object of a Burglary and the manager, rather
than the individual tenants/renters, wil most likely report the offenses to the police, the agency
should report the Burglary to the FBI’s UCR Program as a single incident.”32 Under the updated
rule, law enforcement should report an offense at a qualifying location as a single incident against
a single object while also recording the number of units affected.
As discussed previously, perhaps the most significant change between SRS and NIBRS is the
elimination of the hierarchy rule. Under this rule, when a law enforcement agency reported data
about a given incident to SRS, in almost al cases it was only able to report one offense per
incident.33 If multiple offenses occurred within a single incident, only the most serious crime (per
the SRS hierarchy) was reported to the FBI.34 This rule likely stemmed from the constraints of
data collection when SRS was stil a paper-based reporting system. The effect of the hierarchy
rule has been to undercount the number of crimes that are reported to law enforcement agencies.35
NIBRS does not apply the hierarchy rule and al ows law enforcement to report up to 10 co-
occurring offenses per single incident.36 There has been some concern that the elimination of the
hierarchy rule may make it appear as if there has been a large increase in crime; however, present
data do not support this conclusion (see more discussion of this in the “Influence of the Shift to
NIBRS on Crime Rates” section).
The Office for Victims of Crime (OVC) has outlined several additional benefits of NIBRS for
crime victims.37 First, the elimination of the hierarchy rule is expected to reveal information on
co-occurring victimizations. In SRS, it would not have been possible to study incidents involving
multiple offenses perpetrated against the same victim or victims. NIBRS also al ows for improved
examination of incidents involving multiple offenders. Data on co-offenders might al ow law
enforcement and criminologists to better understand juvenile offenders, who are more likely than
adults to offend in groups.38 In addition, NIBRS collects information about weapons used by
offenders (e.g., firearm, automatic rifle, knife/cutting instrument, motor vehicle, poison,

object, or oral penetration by a sex organ of another person, without the consent of the victim.”
29 U.S. Department of Justice, Federal Bureau of Investigation, National Incident-Based Reporting System (NIBRS),
https://www.fbi.gov/services/cjis/ucr/nibrs (hereinafter, “ FBI, NIBRS”).
30 FBI, NIBRS.
31 NIBRS User Manual, p. 19.
32 NIBRS User Manual, p. 19.
33 SRS User Manual. T here are a few exceptions to the hierarchy rule. Arson and both forms of human trafficking are
always counted regardless of whether multiple offenses occurred (p. 23). Motor vehicle theft is a special case of
larceny-theft, and is therefore counted in a separate category (pp. 25 -26). Justifiable homicide, “ by definition, occurs in
conjunction with another offense(s). T herefore, the crime being committed when the justifiable homicide took place is
reported as a separate offense.” (p. 30).
34 Are You Ready?.
35 Are You Ready?.
36 Are You Ready?.
37 U.S. Department of Justice, Office of Justice Programs, Office for Victims of Crime, Eight Benefits of NIBRS to
Victim Service Provides, https://ovc.ojp.gov/sites/g/files/xyckuh226/files/pubs/NIBRS/index.html.
38 U.S. Department of Justice, Office of Justice Programs, National Institute of Justice, Co-Offending and Patterns of
Juvenile Crim e, December 2005, https://www.ncjrs.gov/pdffiles1/nij/210360.pdf, p. ii.
Congressional Research Service

4

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

fire/incendiary device, or explosives) that was not included in SRS.39 Collecting this type of data
may aid law enforcement initiatives and legislation regarding weapons used during the
commission of a crime. Collection of more granular crime data, including victim demographics
and bias motivation, may help in developing better victims’ services programs and legislation.
NIBRS collects data on the age of victims, whether the offense was cleared (e.g., was someone
arrested), as wel as the relationship between the victim and offender.40 NIBRS also al ows
agencies to identify up to five co-occurring bias motivations per offense type when a crime
appears to be driven by an offender’s biases.41 The measured biases include
race/ethnicity/ancestry, religion, sexual orientation, disability, gender, and gender identity. Each
of these data elements may advance research on crime victimization and perhaps improve
resources and outcomes for victims.
Although domestic violence offenses such as elder abuse and intimate partner violence are not
listed as Group A or Group B offenses, the data on victim-offender relationships wil al ow
researchers and law enforcement agencies to examine these types of offenses. NIBRS data can be
filtered by age, gender, race, weapon, location, and offense type, as wel as by the following
victim-offender relationships: spouse, parent/step-parent, sibling/step-sibling, child/step-child,
grandparent, grandchild, in-law, boyfriend/girlfriend, child of boyfriend/girlfriend, homosexual
relationship, ex-spouse, and other family member.42 These data permit more precise analyses,
such as identifying common correlates or predictors for elder abuse, which were not possible
using SRS data. This precision may, in turn, help in developing more-targeted policy programs or
intervention strategies. However, these crimes are often unreported or underreported and, as a
result, the National Crime Victimization Survey is an essential source of information about crimes
that are not reported to the police.43
National Crime Victimization Survey (NCVS)
The Bureau of Justice Statistics (BJS) administers the NCVS, which captures information about criminal
victimization in the United States. The NCVS is not a part of UCR data col ection, but the survey addresses
important gaps in the understanding of crime in the United States. The NCVS is conducted via interviews with a
subset (i.e., sample) of the population about the nature of any victimizations (i.e., frequency, characteristics, and
consequences) they may have experienced. This interview-based methodology enables the NCVS to include data
on crimes both reported and unreported to law enforcement. The survey provides key information about crime,
including crimes that were not reported to law enforcement.44 Thus, the NCVS is a valuable data source in
addition to UCR when examining the totality of crime in the United States.45 As with the NCS-X, statistics
generated via sampling procedures are subject to error arising from the nature of the sample and the
participants.46

39 NIBRS User Manual, pp. 92-93.
40 NIBRS User Manual, pp. 119, 67, and 151.
41 NIBRS User Manual, pp. 78-79.
42 See the EZANIBRS system for an example of these filters at https://www.ojjdp.gov/ojstatbb/ezanibrsdv/asp/
selection.asp.
43 Darlene Hutchinson, Fewer than Half of Victims Report Violent Crimes, U.S. Department of Justice, Office of Justice
Programs, December 14, 2017, https://www.ojp.gov/sites/g/files/xyckuh241/files/archives/blogs-2017/2017-blog-
ncvs.htm.
44 U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, Criminal Victimization, 2019,
Summary, September 2020.
45 See CRS Report RL34309, How Crime in the United States Is Measured, by Nathan James and Logan Rishard
Council, pp. 17-31.
46 See CRS Report RL34309, How Crime in the United States Is Measured, by Nathan James and Logan Rishard
Council, pp. 26-27.
Congressional Research Service

5

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

Potential Issues Related to the NIBRS Transition
Influence of the Shift to NIBRS on Crime Rates
As noted, the elimination of the hierarchy rule has raised concerns that using NIBRS data to
calculate crime rates might make it appear that crime has increased. In particular, reporting co-
occurring crimes during an incident, as opposed to only reporting the most serious crime, may
lead to a perception that crime rates have gotten worse rather than that the reporting of crime is
now more complete. However, these concerns may not be warranted in many situations. First, the
shift to NIBRS wil not occur al at once. The adoption of NIBRS has been gradual and
geographical y diffuse, and most states have already implemented it. Although the FBI’s annual
crime report, “Crime in the United States,” continued to report data in the SRS format and with
the hierarchy rule in place up until the most recent report,47 the FBI has also created reports using
NIBRS data at the national level and for individual states.48 These FBI publications and local
reports from agencies that have been collecting NIBRS format data for longer periods may
provide agencies with baselines for comparison about how adopting NIBRS may influence their
crime data.
Two studies have demonstrated that implementing NIBRS did not result in significant increases
in crime rates. These studies were published in 2000 and 2014, and thus suggest the stability of
these results across a significant span of time.
The first study, published by BJS in 2000, included 1,131 law enforcement agencies.49 The study
compared the crime rates calculated using SRS (i.e., with the hierarchy rule in place and hotel
rule not applied to storage facilities) to those obtained using NIBRS and found, on average, a 2%
increase in the overal crime rate. The murder rate remained unchanged, which was to be
expected as it was at the top of the SRS hierarchy. Rape, robbery, and aggravated assault rates
increased, on average, less than 1% when using NIBRS data. The greatest changes were observed
for larceny and motor vehicle theft rates (3.4% and 4.5% higher, respectively). These increases
were likely attributable to the absence of a hierarchy rule.50 The burglary rate was, on average,
0.5% lower in NIBRS (the authors credited this shift to changes in the hotel rule).51 The study
also examined the differing influence of NIBRS in jurisdictions with varying levels of crime. The
results indicated that jurisdictions with relatively high rates of crime may not observe significant
changes, but NIBRS may have more of an influence in smal er or lower-crime jurisdictions.
According to the authors,
a jurisdiction that experienced in a year two robberies, one of which was in conjunction
with a murder, would count one robbery under Summary UCR and two under NIBRS.
Though the actual count differed by one, the percent difference was 100%. Such

47 Department of Justice, Federal Bureau of Investigation, 2019 Crime in the United States, Violent Crime – Data
Collection, https://ucr.fbi.gov/crime-in-the-u.s/2019/crime-in-the-u.s.-2019/topic-pages/violent -crime.
48 For example, see U.S. Department of Justice, Federal Bureau of Investigation, 2019 National Incident-Based
Reporting System, https://ucr.fbi.gov/nibrs/2019.
49 U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics Special Report, Effects of NIBRS
on Crim e Statistics, July 2000, p. 2 (hereinafter, “ BJS, Effects of NIBRS on Crim e Statistics”).
50 BJS, Effects of NIBRS on Crime Statistics, pp. 7-8.
51 BJS, Effects of NIBRS on Crime Statistics, p. 5.
Congressional Research Service

6

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

jurisdictions should rely on the actual numbers rather than percent differences to express
changes in measurement or over time.52
The second study was published by the FBI in 2014.53 This study examined the 6,299 agencies
reporting to NIBRS in 2014 and compared the difference in national-level crime rates that
resulted from the application or elimination of the hierarchy rule. Overal , the national crime
rate54 increased by 2.1% when comparing NIBRS to SRS, which was attributed to the joint
influence of the elimination of the hierarchy rule and the ability to report co-occurring offenses.55
This study found the following differences in offense-specific crime rates when comparing
NIBRS to SRS: less than a 0.1% increase for rape, a 0.6% increase for robbery and aggravated
assault, a 1.0% increase for burglary, a 2.6% increase for larceny, and a 2.7% increase for motor
vehicle theft. This is consistent with the results reported in the prior study. In general, these
results indicate that, on average, crime rates do not greatly increase between NIBRS and SRS.
The domain in which increases appear to be the largest are property crimes.
Taken together, these results suggest that NIBRS does not significantly distort crime rates at the
national level, but local agencies, especial y in low-crime areas, may see notable increases in the
reported numbers and rates of some crimes. There are strategies law enforcement can use to help
the public understand NIBRS data, and any related crime rate increases, in their proper context.
One strategy is to present the raw counts of criminal offenses rather than percentages. This way,
the public may better understand that a large percentage increase does not necessarily indicate a
significant uptick in actual crime.56 Another strategy is for law enforcement agencies to present
several years of data in both NIBRS and SRS formats to demonstrate how crime rates would have
looked using both methods.57 This approach may “demonstrate what the trend of crime rates
would look like if the agency was stil only reporting in the SRS. The converted data could help
soften and explain the appearance of increased crime while lending even more transparency to the
agency’s crime reporting to the public.”58
Agency Participation
Another concern is that fewer agencies wil participate in NIBRS compared to SRS, and as a
result, data quality wil suffer. As of 2019, every state as wel as Washington, DC, and Puerto
Rico had at least one law enforcement agency that participated in UCR. Although the majority of
states either had at least one law enforcement agency that participated in NIBRS or were
developing a NIBRS-compatible state-based system (e.g., California Incident-Based Reporting
System [CIBRS], the New York State’s Incident-Based System [NYSIBR]), some agencies have
not made the switch. Lower agency participation can have consequences for both understanding
crime in a given year and longitudinal analyses.
Policymakers might consider whether to direct the FBI or BJS to examine where data gaps exist
and whether they systemical y vary by categories such as public safety budgets or rurality. For

52 BJS, Effects of NIBRS on Crime Statistics, p. 3.
53 U.S. Department of Justice, Federal Bureau of Investigations, Uniform Crime Report, Effect of NIBRS on Crime
Statistics, Executive Summary, 2014 (hereinafter, “ FBI, Effect of NIBRS on Crim e Statistics”).
54 T his was calculated using the total counts for murder, rape, robbery, aggravated assault, burglary, larceny, and motor
vehicle theft.
55 FBI, Effect of NIBRS on Crime Statistics.
56 FBI, Effects of NIBRS on Crime Statistics, p. 1.
57 FBI, Effect of NIBRS on Crime Statistics, p.1.
58 FBI, Effect of NIBRS on Crime Statistics, p. 14
Congressional Research Service

7

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

example, in 2019 there were lower levels of NIBRS participation in the Southwest and
Midwest.59 In the Southwest, both Arizona and New Mexico had less than 6% of law enforcement
agencies reporting to UCR using NIBRS, and Texas had about 38% of participating agencies
reporting to NIBRS. Further, these agencies do not cover large proportions of each state’s
population. The agencies reporting to NIBRS cover 6% of Arizona’s population, 37% of New
Mexico’s population, and 23% of Texas’ population. If these states do not increase their
participation in NIBRS now that SRS has been retired, there may be a significant loss of
information about crime in this region. Identifying these gaps is important not only for
appropriately gauging the reliability of conclusions drawn from NIBRS data, but also for
determining where it may be desirable to target resources to increase NIBRS participation.
One barrier to participation in NIBRS could be the cost of setting up more complex data
infrastructure and training staff in the technology. The shift may be especial y difficult for
smal er, or lower funded, agencies to achieve. There are about 18,000 federal, state, and local law
enforcement agencies in the United States, and the sizes of these agencies vary widely from
employing 1 to 30,000 officers.60 Smal town agencies employing 10 or fewer officers are the
most common.61 These types of agencies may struggle to find the financial and technical
resources to implement NIBRS. For example, an initial cost estimate for setting up NIBRS in
Anderson, SC, a town with approximately 27,000 residents and 100 sworn police officers, ranged
from $130,000 to $200,000.62 These costs may be too high for many agencies, and the FBI has
proposed that smal er agencies may benefit from pooling resources or partnering with larger
agencies.63 Federal grant funds were previously made available to help make the shift to NIBRS.
In FY2017, NIBRS conversion was added as an area of emphasis for JAG grants. Following that,
from FY2018 to FY2020, the Bureau of Justice Assistance (BJA) required that JAG recipients
that were not certified as NIBRS-compliant dedicate 3% of any JAG award toward that end.
Access to Federal Grants
A final concern relates to federal grants that base funding on crime data reported to UCR. Several
federal grants, most notably the JAG program, use UCR crime data to calculate al ocations for
state, local, and tribal governments. The JAG program funds criminal justice initiatives in al 50
states as wel as the District of Columbia, Puerto Rico, Guam, the Virgin Islands, American
Samoa, and the Northern Mariana Islands.64 JAG funds are al ocated using a statutorily defined
formula.65 Fifty percent of a state’s JAG al ocation is based on its share of the population and the
other half on the number of violent crimes (i.e., homicide, rape, robbery, and aggravated assault)

59 UCR program participation data.
60 U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, National Sources of Law
Enforcem ent Em ploym ent Data, October 2016, p. 1 (hereinafter, “National Sources of Law Enforcem ent Em ploym ent
Data”).
61 National Sources of Law Enforcement Employment Data, p.1.
62 U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics, National Crime Statistics
Exchange, Estimating Costs for T ransitioning to the National Incident -Based Reporting System (NIBRS),
https://www.bjs.gov/content/pub/pdf/Local%20Agency%20-
%20Estimating%20Cost%20for%20Transitioning%20%20to%20NIBRS_01 232017.pdf.
63 30 Questions, p. 12.
64 See CRS In Focus IF10691, The Edward Byrne Memorial Justice Assistance Grant (JAG) Program , by Nathan
James.
65 34 U.S.C. §10156.
Congressional Research Service

8

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

reported to the FBI66—in particular, “the state’s respective share of the average number of
reported violent crimes in the United States for the three most recent years for which data are
available.”67 Any state that previously submitted data to UCR via SRS can no longer use this
format as of January 2021. As a result, states may lose out on the funds determined by the
reported number of crimes. In acknowledgment of this concern, BJA added the requirements to
JAG grants outlined above. As stated by BJA, “the 3 percent requirement wil assist state and
local jurisdictions in working toward compliance, to ensure they continue to have critical criminal
justice funding available through JAG when SRS is replaced by NIBRS in FY2021.”68 Similar
funding calculations based on violent crimes reported to the FBI are also in place for the DNA
Capacity Enhancement and Backlog Reduction (CEBR) program69 as wel as the Debbie Smith
DNA Backlog Grant program.70

66 See CRS In Focus IF10691, The Edward Byrne Memorial Justice Assistance Grant (JAG) Program , by Nathan
James.
67 See CRS In Focus IF10691, The Edward Byrne Memorial Justice Assistance Grant (JAG) Program , by Nathan
James.
68 U.S. Department of Justice, Bureau of Justice Statistics, Edward Byrne Justice Assistance Grant (JAG) Program
Factsheet, p.2, https://bja.ojp.gov/sites/g/files/xyckuh186/files/publications/2018-JAG-Fact-Sheet.pdf.
69 U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Assistance, FY2020 DNA Capacity
Enhancem ent for Backlog Reduction (CEBR) Program (Form ula) , FY2020 Grant Solicitation, https://bja.ojp.gov/
funding/opportunities/bja-2020-18413.
70 34 U.S.C. §40701(c).
Congressional Research Service

9

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

Appendix. SRS and NIBRS Offense Lists
Summary Report System (SRS)71
Part 1 Offenses
(Note: The order of Part I offenses here also reflects the order in which the hierarchy rule was
applied).

 Criminal Homicide
 Rape
 Robbery
 Aggravated Assault
 Burglary
 Larceny-theft (except motor vehicle theft)
 Motor Vehicle Theft
 Arson
 Human Trafficking, Commercial Sex Acts
 Human Trafficking, Involuntary Servitude
Part 2 Offenses
 Other Assaults (simple)
 Forgery and Counterfeiting
 Fraud
 Embezzlement
 Stolen Property (buying, receiving, or possessing)
 Vandalism
 Weapons (carrying, possessing, etc.)
 Prostitution (including commercialized vice, assisting or promoting prostitution,
and purchasing prostitution)
 Sex Offenses (except rape and prostitution offenses)
 Drug Abuse Violations
 Gambling
 Offenses Against the Family and Children
 Driving Under the Influence
 Liquor Laws
 Drunkenness
 Disorderly Conduct

71 U.S. Department of Justice, Federal Bureau of Investigation, Crime Justice Information Services Division, Uniform
Crime Reporting Program, Sum m ary Reporting System (SRS) User Manual, pp. 20-22.
Congressional Research Service

10

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

 Vagrancy
 Al Other Offenses
 Suspicion
 Curfew and Loitering Laws (persons under 18)
 Runaways (persons under 18)72
National Incident-Based Reporting System (NIBRS)73
Group A Offenses
 Animal Cruelty
 Arson
 Assault Offenses
 Aggravated Assault
 Simple Assault
 Intimidation
 Bribery
 Burglary/Breaking & Entering
 Commerce Violations
 Import Violations*
 Export Violations*
 Federal Liquor Offenses*
 Federal Tobacco Offenses*
 Wildlife Trafficking*
 Counterfeiting/Forgery
 Destruction/Damage/Vandalism of Property
 Drug/Narcotic Offenses
 Drug/Narcotic Violations
 Drug Equipment Violations
 Embezzlement
 Espionage*
 Extortion/Blackmail
 Fraud Offenses
 False Pretenses/Swindle/Confidence Game
 Credit Card/Automated Tel er Machine Fraud
 Impersonation

72 Runaway has not been a required-reporting offense in UCR since 2009, as it is not a criminal offense in all
jurisdictions. Runaway data are stored in UCR when reported but these data are not reported by the FBI in UCR
databases; the FBI no longer publishes information on runaways as a Part II crime.
73 NIBRS User Manual, pp. 10-14.
Congressional Research Service

11

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

 Welfare Fraud
 Wire Fraud
 Identity Theft
 Hacking/Computer Invasion
 Money Laundering*
 Fugitive Offenses
 Harboring Escapee/Concealing from Arrest*
 Flight to Avoid Prosecution*
 Flight to Avoid Deportation*
 Gambling Offenses
 Betting/Wagering
 Operating/Promoting/Assisting Gambling
 Gambling Equipment Violations
 Sports Tampering
 Homicide Offenses
 Murder and Nonnegligent Manslaughter
 Negligent Manslaughter
 Justifiable Homicide (Not a Crime)
 Human Trafficking Offenses
 Commercial Sex Acts
 Involuntary Servitude
 Immigration Violations
 Il egal Entry into the United States*
 False Citizenship*
 Smuggling Aliens*
 Re-entry about Deportation*
 Kidnapping/Abduction
 Larceny/Theft Offenses
 Pocket-picking
 Purse-snatching
 Shoplifting
 Theft From Building
 Theft From Coin-Operated Machine or Device
 Theft From Motor Vehicle
 Theft of Motor Vehicle Parts or Accessories
 Al Other Larceny
 Motor Vehicle Theft
 Pornography/Obscene Material
 Prostitution Offenses
Congressional Research Service

12

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

 Prostitution
 Assisting or Promoting Prostitution
 Purchasing Prostitution
 Robbery
 Sex Offenses
 Rape
 Sodomy
 Sexual Assault With An Object
 Fondling
 Incest
 Statutory Rape
 Failing to Register as a Sex Offender*
 Stolen Property Offenses
 Treason*
 Weapon Law Violations
 Weapon Law Violations
 Violation of National Firearm Act of 1934*
 Weapons of Mass Destruction*
 Explosives*
Group B Offenses
 Bad Checks
 Bond Default
 Failure to Appear*
 Curfew/Loitering/Vagrancy Violations
 Disorderly Conduct
 Driving Under the Influence
 Drunkenness
 Family Offenses, Nonviolent
 Federal Resources Violations*
 Liquor Law Violations
 Peeping Tom
 Perjury*
 Trespass of Real Property
 Al Other Offenses

*Reported only for federal and tribal law enforcement agencies

Congressional Research Service

13

The National Incident-Based Reporting System (NIBRS): Benefits and Issues

Author Information

Emily J. Hanson

Analyst in Social Policy

Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should n ot be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not
subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in
its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or
material from a third party, you may need to obtain the permission of the copyright holder if you wish to
copy or otherwise use copyrighted material.

Congressional Research Service
R46668 · VERSION 2 · NEW
14