It’s time to start collecting stop data: A case for comprehensive statewide legislation

The Policing Project is partnering with the California Department of Justice and the Center for Policing Equity to develop a national guidebook on best practices for collecting, analyzing, and responding to data about traffic and pedestrian stops by law enforcement, a critical but often overlooked aspect of policing. Before we release our stop data guidebook in 2020, we begin with this state of the field report to show both the importance of stop data collection and the ways in which many current laws come up short.

Why Stop Data Matters

Police officers in the United States pull over at least 50,000 drivers every day, making the traffic stop a key element of modern policing and the most common interaction that members of the public have with police officers. Even beyond the frequency, there are many reasons to pay attention to stops. For starters, fines and fees from stops can result in serious financial burdens for individuals, and research suggests that both traffic stops and pedestrian stops disproportionately burden people of color.

Further, traffic and pedestrian stops have been linked to racially discriminatory practices, including racial profiling, as well as illegal searches and use of force incidents. Some studies have shown substantial gender and racial differences in how individuals perceive these interactions with police officers, and for minority groups, stops may be associated with increased stress, trauma or feeling of second-class citizenship, unfairness, and frustration. Evidence also shows that smaller police departments with fewer resources are less likely to collect stop data and less accountable to the public, suggesting that rural communities may be least represented by existing stop data and yet the most impacted by stops.

The truth is there is a lot we still don’t know about traffic stops. For example, while stops are often employed by police departments as a crime-fighting tool, the evidence that stops actually reduce crime is unclear at best. A recent Policing Project study in Nashville showed traffic stops were not an effective strategy for reducing crime in the city (and were resulting in racial disparities and social costs), prompting a major change in policing strategy. Other studies have shown an overemphasis on fines and fees can make police departments less effective at solving violent crimes.

What we do know is that when the public has information about traffic stops, it can lead to changes in state laws. For example, in North Carolina, accusations of racial profiling led to the passage of a state law requiring the collection of traffic stop data, which revealed massive racial disparities in the stops. Several jurisdictions revised their practices as a result, including requiring officers to obtain written consent before searching a car during a traffic stop.

However, as we will show here, stop data collection laws, even when they do exist, are far from perfect. Many don’t cover both pedestrian and traffic stops, some exempt agencies from making their data public, and some contain no enforcement mechanism to ensure departments are complying. In other cases, the data itself is simply so incomplete as to be practically useless.

Stop Data Collection State by State

Currently there are 19 states that (for the most part) mandate collection of data on every law enforcement initiated traffic stop–what we refer to here as a “comprehensive” stop data law. However, just because a state has a “comprehensive” law, doesn’t mean that it’s an effective or thorough one.

As shown in the map below, 29 states have no comprehensive stop data requirements and two, Florida and Alabama, have stop data collection laws that only apply to certain types of stops (we refer to these as "incomplete laws" on our map). Of the 19 states that require stop data collection, only three—California, Illinois, and Oregon—require it for all vehicle and pedestrian stops.

All of these 19 states require the collection of some driver information for vehicle stops, but even this can vary substantially from state to state, with some states only capturing the driver’s race, while others record age, gender identity, English-language ability, and more.

Stop information, which can include the time, date, location and basis for the stop, and the results of the stop, which can encompass any actions taken by officers such as use of force, the basis and results of any search or seizure, and if a citation was issued or an arrest made, is collected in sixteen of these states, but to varying degrees. Three of the 19 states—Montana, South Carolina and Washington—do not collect any information on the stop itself or its results.

Notably fewer states also require collection of officer information, which most often includes an identifying number for the officer, but can also include other data such as the officer’s specific assignment. Officer information is only collected in California, North Carolina, Connecticut and Kansas.

To demonstrate how widely states can vary, the table below compares data collection requirements in six states, ranging from the most robust law in California to one of the least robust in Washington.

Highlights from Our Findings

States with the most comprehensive laws, those requiring a wide breadth of data collection, are better able to understand and effectively address the realities of stops. For example, data on a driver’s English-language ability or the location of the encounter, as well as the actions of the police officer, could potentially show if certain neighborhoods are disproportionately affected by stops or if non-native English speakers are more likely to have their vehicles searched. City officials and police departments can use this information to modify relevant policy and inform officer training to address potential inequalities.

By far the nation’s most comprehensive stop data collection requirements are those recently enacted in California, which are still being rolled out across the state. The statute covers both traffic and pedestrian stops, and officers must indicate their perception of the driver’s English-language ability, gender identity, and any mental or physical disabilities. Officers must also record other information about the stop including if force was used, all actions taken by the officer, the basis for any search, any contraband discovered, any property seized, and the basis for any property seizure. Importantly, the officer also must record his or her own information including assignment information, ID number, and years of experience.

Illinois’ law also stood out for its emphasis on analysis of the collected data. The state has had a comprehensive stop data law since 2004, and recently passed an amendment to make the requirements of the law permanent. While the original bill required all law enforcement agencies to report their data to the Illinois Department of Transportation, which published an annual report summarizing the data, the recent amendment also established a Traffic and Pedestrian Stop Data Use and Collection Task Force under the purview of the Illinois Criminal Justice Information Authority (instead of IDOT). This task force will be made up of researchers as well as representatives from the police department, government agencies, and community organizations, and will study the best practices of collecting, compiling, and analyzing stop data and report its findings to the General Assembly every three years. The ultimate purpose of this rigorous data analysis is to identify statistical significant patterns that can illuminate the areas of policing that need to be improved.

Another crucial element in an effective stop data law is an enforcement mechanism to incentivize law enforcement agencies to comply. Several states have compliance stipulations written into their statutes. For example, if an agency in Texas fails to comply with the stop data law, it would be liable to the state for up to $5,000. In North Carolina, the penalty for failing to submit data is ineligibility for any state grants. And there is evidence that these measures are working. Missouri, which has a noncompliance penalty, received stop data from 97.6% of its law enforcement agencies in 2018. In contrast, a recent report from the Southern Poverty Law Center indicates that in Louisiana, a state without an enforcement mechanism, only two of the 109 law enforcement agencies required to submit stop data could produce records showing they had done so.

While having any state legislation requiring stop data collection is an important first step to improving policing and rectifying inequalities, it is important to note that programs that do not generate comprehensive information produce data that is relatively useless for illuminating systemic traffic stop practices. For example, Alabama has four separate statutes that mandate officers record when minority groups are stopped. However, the statues only cover very specific types of stop— when children are not properly restrained, when occupants aren’t wearing seatbelts, when drivers under 18 are stopped, and when drivers are texting behind the wheel. Further, if officers only record stops of minority groups, there is no information to determine how often these groups are stopped as compared to the total population, making it difficult to identify inequalities and inform efforts to rectify them.

In the absence of a law, another means by which a state can gather stop data is through a voluntary program, such as the program currently used by the Ohio Collaborative Community-Police Advisory Committee (commonly referred to as the Collaborative). This twelve-person body of law enforcement experts and community members was established in 2015 by executive order of Governor Kasich. The Collaborative uses the incentive of certification, a public designation developed by the Collaborative to separate law enforcement agencies that meet its standards from those that do not, as a means to encourage police reform. To meet the Collaborative’s standard for bias free policing, police departments must engage in training around bias, issue corrective action if bias is discovered, collect race and gender information on all officer-initiated traffic conduct, and publish an annual review of all data. However, there is no formal penalty for agencies that do not receive a certification, and the Collaborative indicates that only 21% of law enforcement officers in Ohio work for agencies that have not undergone certification. While this voluntary program is better than nothing, a law is the gold standard.

Our Stop Data Guidebook Project

While some states are taking steps toward collecting comprehensive stop data, the majority are falling behind. As we have seen, there are a myriad of ways that stop data laws can come up short: when they collect data on traffic stops and ignore pedestrian stops; when they fail to include penalties for noncompliance; or when they place too much emphasis on the collection of the data and not enough emphasis on data analysis and publication.

Creating a comprehensive stop data law is an extremely worthwhile task; however, it is also a complex and demanding one, which is why the Policing Project, the Center for Policing Equity, and the California Department of Justice are working together to draft a stop data guidebook. We hope that with the help of this guidebook, state legislatures will adopt stop data legislation and practices to ensure that police are effectively directing their resources and are not disparately impacting rural residents, low-income individuals, and communities of color.

Our stop data guidebook will be released in early 2020.

Research for this post was done by Policing Project externs Hannah Rose Anderson and Alexa Perlmutter.