NIBRS Noncompliance Has Become More of a Small Agency Problem

We’ve been talking about crime trends a lot over the last few weeks, so I thought it’d be a good time to step back and take a look at the nuts and bolts of crime data this week. Back in July I wrote a post about a change in reporting that the FBI was allowing to enhance the estimative power of its national crime estimates.

I described the issue thusly:

Since 1930, agencies have submitted data to the FBI covering 7 major categories of violent and property crime – arson was added in 1979 – under a system called the Summary Reporting System (SRS). This system was good at capturing overarching crime figures but was somewhat lacking in depth. In the late 1980s a new system was developed called the National Incident-Based Reporting System (NIBRS) which brings a greater level of depth to crime data and modifies what data is reported to allow for more accurate crime counts nationwide.

NIBRS would be a far superior crime data reporting system if one was designing a system from scratch, but a large portion of the country does not use NIBRS to report data even decades after the system was introduced. Only about 1/3 of agencies nationwide were reporting data via NIBRS when the FBI announced in 2015 that it would not allow agencies to submit data via SRS, only NIBRS starting in 2021.

Many agencies did make the transition to NIBRS in the ensuing 6 years, but by 2021 only around 2/3 of agencies were NIBRS-compliant. Just over half of the US population was covered by an agency that submitted a full year of data for 2021.

NIBRS compliance in 2022 increased to over 70 percent of agencies, and I would expect that percentage to jump again a fair amount when 2023’s figures are reported later this year. It took a few years, but the FBI has essentially solved most of the NIBRS compliance issue, or at least solved it to the point where the national estimates are not at risk of needing an asterisk on the historical record. Having 80 or 85 percent of the population reporting is way less problematic for national estimates than having 60 percent — especially when another 10 to 15 percent is reported via the old system.

The biggest issue may be mostly solved, but looking deeper into the FBI’s data on NIBRS participation points to a new issue developing that could hinder the nation’s ability to reach the overarching goal of NIBRS reporting at the 90 to 95 percent of agencies that reported data via the old system each year. The crux of the matter is that bigger cities and counties are becoming NIBRS compliant at acceptable (my judgement) levels while compliance in smaller cities and counties is still comparatively low and not growing as fast.

To show this I took FBI agency data over the six years between 2017 and 2022 (2023 data isn’t available yet) and calculated the share of agencies that were NIBRS compliant grouped by population size. It's not a perfect measurement and is a relatively rough estimate, but it shows the trend clearly.

Cities of all sizes started at roughly the same place in 2017 in terms of NIBRS compliance. While 80 percent or so of larger police departments were NIBRS compliant in 2022, just over half of smaller police department were.

The same pattern holds true with rural and metro county agencies (note that there aren’t a ton of small metro county agencies).

This issue has implications for how (or even if) NIBRS compliance can reach close to the levels of SRS reporting. I’m undoubtedly oversimplifying, but my guess is that agencies that are not close to being NIBRS compliant probably need some help getting there at this point. Some agencies may need more funding to purchase a new Records Management System while others would need technical training of staff on how to use NIBRS. Making the NIBRS switch for many agencies is going to require a proactive push (financial and otherwise) from outside parties.

But here’s the problem:

New York City, NY (population 8.5 million) and Littleville, AL (population 1,040) each have one police department. Providing outside assistance to achieve NIBRS compliance requires a certain floor of resource allocation no matter who is being provided the assistance. Obviously helping a large department achieve compliance would require far more resources than a small one (and Littleville is already NIBRS compliant!), but if help is available to only a finite number of agencies then it’s more efficient to add a few larger agencies than many more smaller cities with smaller aggregate population.

Aiding 25 big cities is substantially more efficient for increasing coverage than aiding 100 small cities, but there are way more smaller cities that still need to achieve NIBRS compliance than bigger city departments. A roughly similar number of Americans live in big cities of 250,000 or more compared to small cities of under 25,000 (62 million vs 52 million, give or take a bit), but there were 89 cities with 250,000 people or more that reported data to the FBI in 2022 compared to nearly 10,000 cities with under 25,000 people.

Substantially fewer people live in small counties compared to big ones, but there are more law enforcement agencies in small counties. Around 5 million people live in small counties of 10,000 or under compared to over 90 million people living in big counties, but there were 2,300 agencies from small counties compared to 1,700 from big counties reporting data to the FBI in 2022.

Getting larger agencies NIBRS compliant is hugely advantageous for ensuring accurate national crime data collection and reporting efforts. This potentially creates more of an incentive for assisting larger agencies with gaining compliance, possibly at the expense of smaller agency efforts.

There are many advantages to smaller agencies becoming compliant, especially for academics and researchers, but those advantages might be harder to come by if larger agencies are almost all compliant and smaller agency compliance plateaus at a significantly lower rate.

Getting smaller agencies to match the compliance level of larger agencies is a better problem to have than getting compliance from all agencies above 50 percent. But it’s still a potential issue that will require attention from those interested in crime data as time goes on.