Should California ban police from making traffic stops for minor violations?
So-called ‘pretext stops’ have come under scrutiny in recent years, as several city police departments have moved to limit them. But are they a key to keeping crime low?
Today’s Debate
California law enforcement officers make more than 3 million traffic stops every year, due in part to the incredibly large number of traffic laws and motor vehicle regulations. Historically, police officers have been given the authority to pull over anyone who is violating one of those laws. Police officers have used this authority to justify pulling over and then searching the vehicles of those they suspect of more egregious crimes.
For example, a cop pulls over a car for an outdated registration because she believes that the driver may have been involved in a recent shooting and have illegal firearms in the vehicle. Once pulled over, the cop asks the driver if she can search the car. Not thinking he has a choice, he consents, as most drivers do. The cop searches the car, which may lead them to find incriminating evidence.
This is a pretext stop because the officer stopped the driver for a minor violation expecting it to lead to a serious arrest. Pretext stops became a component of broken windows policing - the focus on removing visible signs of crime, anti-social behavior, and civil disorder in the 1990s:
“You had the kind of powder keg that built up in L.A. through the ’80s and ’90s as a lot of policymakers and other decision-makers in the Southland and L.A. decided that the way to fight rising crime in L.A. was by allowing more pretextual stops, more investigative searches, more stop-and-frisk on wheels, more broken windows policing, zero tolerance policing.”
As pretext stops became more common, legal challenges arose, leading to the 1996 Supreme Court case, Whren v. United States. In this case, the Court ruled that pretext stops could continue:
“The temporary detention of a motorist upon probable cause to believe that he has violated the traffic laws does not violate the Fourth Amendment’s prohibition against unreasonable seizures, even if a reasonable officer would not have stopped the motorist absent some additional law enforcement objective… Subjective intentions play no role in ordinary, probable-cause Fourth Amendment analysis.”
While pretext stops have drawn criticism at various points over the last 25 years, they entered the spotlight again after George Floyd’s death because of the history of racial bias in pretext stops.
Police in San Francisco, Oakland, and Los Angeles, and city officials in Berkeley, have already implemented some restrictions on officers’ authority to make these stops or are working on them. A number of other jurisdictions outside California have also begun to implement reforms limiting traffic stops, including Virginia and Lansing in 2020, Philadelphia, Pittsburgh, and Minneapolis in 2021, and Oregon and Seattle in 2022. Last May, President Biden weighed in on the topic, issuing a nationwide executive order calling on police to end “discriminatory pretext stops.”
I cover this debate this week because the San Francisco Police Commission voted 4-2 to approve a ban on conducting traffic stops for 9 traffic violations this week - and 2 California state senators say they plan to introduce legislation this January aimed at limiting police authority to make pretext stops.
Argument in Brief
Should California ban officers from conducting pretext stops for minor traffic violations?
Pretext stops are racially biased
Pretext stops are an inefficient use of already inadequate law enforcement resources
Minor traffic violations can be enforced in other ways
Traffic deaths and injuries will increase
Pretext stops are already infrequent and on the decline
We shouldn’t ban police from enforcing the law
California should not ban pretext stops, but it should prepare to implement the Los Angeles Police Department’s traffic stop policy statewide. The LAPD’s new policy allows pretext stops, but requires officers to explain on their body camera why they believe the stop will lead to evidence of a more serious offense before approaching a vehicle. Recent policy changes in Los Angeles, San Francisco, and a number of other Californian cities offer a helpful laboratory for evaluating the impact of reducing pretext stops. We’d be wise to wait 1-2 years to learn from them before making any changes at the state level.
Case For:
Pretext stops are racially biased
In its 2022 annual report, California’s Committee on Revision of the Penal Code made this claim:
“California law enforcement officers make more than 3 million traffic stops every year, with disturbing racial disparities in who is stopped.”
According to California’s Racial and Identity Profiling Advisory (RIPA) Board, in 2020, Black and Hispanic people were stopped 112% and 9%, respectively, more frequently than expected based on their proportion of California’s residential population, while white people were stopped 7% less frequently than expected.
This imbalance in stops occurs for many of the most common pretextual stops, including no registration, displaying license plates incorrectly, problems with lighting equipment, and something obstructing one’s window.
Other analyses show similar imbalances as well. A San Francisco Chronicle analysis found that black people in San Francisco were 4.4 times more likely to be stopped than white people and 10.5 times more likely to be pulled over in a pretextual stop than white people. In Oakland, black people were 5.3 times more likely to be stopped. In Sacramento, black people were 3.7 times more likely to be stopped. And these disparities increased in 11 of the state’s biggest law enforcement agencies between 2019 and 2020.
Los Angeles City Councilman Marqueece Harris-Dawson describes the frequency of these stops for black people this way:
“I don't know of an African American male driver, (and) I know very few Latino male drivers, who don't have half-a-dozen stories about being stopped by police for reasons that didn't make sense.”
This isn’t a California-specific phenomenon either. An analysis of over 8M traffic stops in Washington State following a court decision to allow more pretextual stops found a “statistically significant increase in traffic stops of drivers of color relative to white drivers.”
Further, black people aren’t just pulled over more frequently. They are searched 2.2 times more frequently than white people.
Are officers’ disproportionate stopping of black drivers justified by higher rates of finding evidence of more serious crimes?
The most recent RIPA annual report found that the rate of discovering anything illegal when conducting a consented search was just 1% higher for black people than white people (26% compared to 25%). This insignificant difference in discovery rate suggests that police are not justified in stopping black people at a considerably higher rate.
The racial disparity in pretext stops is likely to have consequences too. William Briggs, President of the Los Angeles Police Commission, describes the effect:
“The current practice of pretextual stops only serves to alienate whole segments of our community from law enforcement.”
Los Angeles City Councilman Marqueece Harris-Dawson agrees, arguing that public trust in the police is "so easily degraded when a person is stopped and they can't figure out why they were stopped or that the reason they were given just doesn't add up for them."
Consistent with these comments, an analysis of responses to the Police-Public Contact Survey found that people who had been stopped by an officer in the previous year were less likely to contact the police for assistance or to report a neighborhood problem.
In addition, many of the black people who are pulled over are not just being stopped either. Nearly 20% are searched, 18% are detained on the curb or in a patrol car, and 15% are handcuffed - all at nearly twice the rate white people experience these additional police actions. These additional officer actions turn what may start as an inconvenience into a “frightening, humiliating, and even dangerous” experience. A systematic review of traffic stop studies published this year found the following negative consequences for individuals experiencing traffic stops:
46% increase in the odds of a mental health issue
36% increase in the odds of a physical health issue
Significantly more negative attitudes toward the police
Significantly higher levels of self-reported crime/delinquency
Pretext stops are an inefficient use of already inadequate law enforcement resources
In 2020, the Commission on Police Officer Standards and Training (POST) issued 4,530 certificates to people who had done what was necessary to become a sworn officer. Last year, the number of certificates fell to just 2,424, a decline of almost 50%.
A resident of the tiny town of Mineral, California describes the impact of this shortage:
“When we called 911 even before they stopped patrolling, they’d say ‘Sorry, we can’t make it, handle it yourself.’ That’s not what someone wants to hear when you’re getting beat up.”
Law enforcement staffing shortages aren’t limited to small rural California towns either. The San Francisco Police Department could be short over 800 officers (roughly a third of full staffing levels) this year with the loss of 300 more officers and only 28 recruits currently in the academy.
National Police Association spokesperson Retired Sergeant Betsy Brantner Smith doesn’t see these shortages ending anytime soon either:
"I think this could be a generational problem. This could go on for years. Even if, let's say, I could flip a magic switch tomorrow, and everyone loved the police and every kid in America wanted to be a cop … it takes nine months to a year from the date of hire for a person to become a police officer."
Sam Blonder, the CEO of a recruiting agency who works with law enforcement agencies, shares a similar view:
“Ask 150 high school kids who wants to be a police officer — you won’t get one that will raise their hand.”
With such dire officer shortages, it’s clear California law enforcement agencies must prioritize the activities that will have the greatest impact on public safety. Given pretext stops’ low arrest rate and mixed impact on traffic safety, maybe they are not worth the time even if they do deliver some results.
San Francisco Police Commissioner Max Carter-Oberstone doesn’t think they are worth the time:
“We’re not taking laws off the books, we are using data to inform what we should be focusing our time on as a police department. It just so happens that pretextual stops are just a very poor use of our scarce resources.”
The Commission’s report goes further, arguing that this time could be used more effectively to reduce crime:
“Expending less time and money on these stops will free up substantial resources that the Department can use on more effective public safety strategies.”
LAPD’s director of constitutional policing and policy, Lizabeth Rhodes, argues that pretext stops are lower priority than other policing activities:
“We have to be more efficient. You know, we want to really enforce public safety, not ticky-tack stuff.”
How much time is spent on pretext stops?
“Data show that officers spend a significant amount of time –nearly 80,000 hours in 2019 – on traffic stops that lead to no enforcement action or discovery of contraband. For local law enforcement departments, 28,000 of those hours were spent on enforcing non-moving violations, which are more likely to be pretextual.”
28,000 is a big number, but there were roughly 33,000 municipal patrol officers in California in 2019, which means that the average local patrol officer spent just 51 minutes in all of 2019 enforcing non-moving violations.
Minor traffic violations can be enforced in other ways
With continued advances in technology, it is becoming increasingly possible for states and municipalities to enforce some traffic violations in an automated or remote way, making it theoretically unnecessary for police to make traffic stops for minor violations. This would render one of the key arguments against a ban on pretext stops - that it could increase traffic deaths and injuries - irrelevant.
To date, traffic monitoring technologies have primarily been used to monitor red-light-running and speeding. Nearly 350 U.S. communities use red-light cameras and more than 150 communities use cameras to enforce speed laws. California is 1 of 22 states that use red-light cameras - and it currently has no laws related to the use of speed cameras.
But these automated approaches to traffic enforcement are not without their challenges, as Jordan Blair Woods, author of Stanford Law article “Traffic Without the Police” explains:
“However, many communities are retreating from those programs in response to community and political backlash. Automated traffic enforcement programs have also been subject to legal challenges in courts with varying success. The strong skepticism of and pushback against automated traffic enforcement raises questions about whether and how technology can assist in reducing reliance on police-initiated traffic stops to enforce traffic laws.”
At this point, technology won’t be able to replace human enforcement, which is why Jordan Blair Woods and others, including the Vera Institute of Justice, argue for citizen (i.e., non-police) traffic monitors to oversee the enforcement of minor traffic violations. Berkeley, California voted to shift traffic enforcement away from the police department in July 2020.
However, this argument either fails to remember the goal of pretext stops or is a covert way to try to eliminate the need for them. The primary goal of pretext stops is to find evidence of more serious crimes, not enforce minor traffic laws. The best technological solutions could do is remove officers’ excuses for pulling people over.
Case Against:
Traffic deaths and injuries will increase
While pretext stops are, by definition, aimed at something other than enforcing minor traffic violations, the argument is still made that these stops prevent accidents themselves and correct driver behavior or vehicle conditions before more serious safety violations occur.
From a research methodology perspective, it can be difficult to prove that traffic stops cause changes in traffic safety. However, a bout of massive layoffs in police officers in Oregon in 2003 created a natural experiment to test this question:
“Due solely to budget cuts, 35 percent of the roadway troopers were laid off, which dramatically reduced citations. The subsequent decrease in enforcement is associated with a significant increase in injuries and fatalities. The effects are similar using control groups chosen either geographically or through data-driven methods. Our estimates suggest that a highway fatality can be prevented with $309,000 of expenditures on state police.”
Another sort of natural experiment involves click-it-or-ticket-it campaigns where law enforcement officers focus on enforcing seat belt rules in a defined geographic area for a designated period of time. An evaluation of these campaigns in Massachusetts found that “tickets significantly reduce accidents and nonfatal injuries.”
An analysis of motor vehicle crashes on 2 Wyoming highways shows something similar:
“The modeling results showed that higher numbers of speeding and seat belt citations reduce the number of crashes significantly.”
However, a 2021 report by the National Institute of Health analyzing the relationship between over 161M police traffic stops in 33 states and motor vehicle crashes from 2004 to 2016 concluded that:
“State patrol traffic stops are not associated with reduced MVC [motor vehicle crash] deaths. Strategies to reduce death from MVC should consider alternative strategies, such as motor vehicle modifications, community-based safety initiatives, improved access to health care, or prioritizing trauma system.”
How do we square these different conclusions? Other more nuanced research suggests that it matters which traffic stops are increased or decreased. For example, one study analyzed the impact of the decision of the police chief in Fayetteville, North Carolina to prioritize safety (e.g., moving violations) stops over investigatory stops and economic (e.g., regulatory or equipment) stops. It found:
“The re-prioritization of traffic stop types by law enforcement agencies may have positive public health consequences both for motor vehicle injury and racial disparity outcomes while having little impact on non-traffic crime.”
By focusing on traffic violations that impact safety the most and ignoring those that have little impact, officers may be able to improve safety. Vision Zero, a San Francisco-based initiative focused on eliminating all severe and fatal traffic crashes, supports a ban of pretext stops for this very reason:
“We know that enforcement of the top five most dangerous driving behaviors was near rock bottom in 2022… The SFPD points to staffing shortages. We hear that, but we also point to the fact that many citations are given for low-level, minor offenses like sleeping in a car, having a broken tail light, or tinted windows.”
The debate in San Francisco transpiring over the last year over whether to ban pretext stops has placed particular emphasis on this question of which traffic stops should be banned:
“In early December, commissioners revised the number of stops that would be banned from 14 to nine, after feedback from members of the public, safety experts and academics.”
This week, San Francisco voted to ban stops for these 9 infractions:
A vehicle that has a rear license plate with the plate number clearly visible
A vehicle that fails to display registration tags or is driving with expired registration of more than one (1) year
A vehicle that fails to illuminate the rear license plate
A vehicle driving without functioning or illuminated rear taillights
A vehicle that is driving without functioning or illuminated rear brake lights
A vehicle that has objects affixed to windows or hanging from the rearview mirror
A vehicle that fails to activate a turn signal continuously for 100 feet before turning
A vehicle that has a person sleeping in the vehicle
Any stop of a pedestrian for an infraction in violation of the California Vehicle Code or San Francisco Transportation Code unless there is an immediate danger that the pedestrian will crash with a moving vehicle, scooter, bicycle, or other device moving exclusively by human power
The 5 it removed from the ban after public comment and further review are:
Failure to display both license plates
Driving without functioning or illuminated headlights
Improperly mounted license plates
Tinted windows
Any parking infraction
The initial research cited suggests that banning enforcement of moving violations would result in more traffic injuries and deaths, but banning non-moving and equipment violations would likely have an insignificant - or even positive - impact on traffic safety.
Crime will increase
While pretext stops may or may not improve traffic safety - depending on the specific stops banned - their primary goal is to reduce crime by enabling officers to catch people with illegal items.
The State’s Committee on Revision of the Penal Code argued in 2022 that:
“Law enforcement openly admit that many of these are ‘pretext stops’ to investigate serious offenses — yet data show these traffic stops rarely result in the discovery of evidence of crime.”
As shared earlier, the annual report from the RIPA Board found that in 2022:
“Overall, officers searched 11.9 percent of individuals they stopped. Officers discovered contraband or evidence from 24.6 percent of individuals they searched.”
This means that of every 100 stops officers made, they discovered illegal items or evidence in 3 stops. This is consistent with an analysis by the LAPD’s inspector general, which found that 2% of traffic stops resulted in arrests. While this rate seems low, it is difficult to know without a comparable benchmark.
However, it’s possible that even if traffic stops aren’t very fruitful in terms of finding contraband or evidence, they dissuade people from committing more serious crimes. To understand this relationship, we need to explore the relationship between traffic stops and crime rates.
A 2018 study of traffic stops in Nashville, Tennessee conducted by the Stanford Computational Policy Lab reported that traffic stops did not lead to reductions in crime:
“Our report further concludes that traffic stops are not an effective strategy for reducing crime. In particular, the MNPD’s [Metro Nashville Police Department’s] practice of making large numbers of stops in high crime neighborhoods does not appear to have any effect on crime.”
An additional Nashville-focused study by the NYU School of Law Policing Project reached a similar conclusion. Los Angeles Police Commission President William Briggs agrees with these findings:
“Those pretextual stops do not result in guns being taken off the streets, those pretextual stops do not result in curtailing murders and curtailing shootings ... there is no data that anyone can point to that establishes that pretextual stops curtail violent crime in our city.”
The LAPD Chief Michel Moore stood behind this assessment when Los Angeles was considering changing its policy for pretext stops earlier this year:
“I've heard thoroughly members of this organization who believe that this policy will stop us from identifying those responsible for violent crime, stop us from identifying those that are carrying weapons, firearms, engaged in street violence. I firmly believe that that is not the case.”
Returning to Nashville, the aforementioned report led to changes in Metro Nashville Police Department training around traffic stops, which resulted in a 90% reduction in traffic stops.
How have crime rates changed during the 2018 to 2022 timeframe? Total crime dropped 5% from 2018 to 2021 (the last year we have city-level crime data), while violent crime increased by 8%. 2022 data from the county where Nashville is located shows a significant increase in overall crime, topping 2018 levels, and another increase in violent crime. This doesn’t prove that the reduction in traffic stops led to an increase in crime or refute the much more rigorous analysis done by NYU and Stanford, but, at a minimum, we should be wary to conclude reducing traffic stops has no effect on crime.
While Nashville’s correlation data doesn’t prove crime will increase if we ban pretext stops, a meta-analysis of 40 studies on police-initiated pedestrian stop interventions published this year found that such interventions were associated with a statistically significant 13% reduction in crime in the relevant areas and a distribution of crime reduction benefits to a broader area.
Pretext stops are already infrequent and on the decline
If pretext stops make up an insignificant portion of traffic stops and are declining on their own, then it may not be worth pushing through a new policy and then re-training officers. With local patrol officers spending just 51 minutes per year on pretext stops, it could be that this is not worth addressing.
In 2022, moving violations accounted for 73% of all traffic stops in California. A San Francisco Chronicle analysis of traffic stops between mid-2018 and mid-2022 found that 20% of all stops were made for the 14 violations the Police Commission originally proposed keeping officers from enforcing. However, pretext stops for these violations dropped dramatically between mid-2019 and mid-2020 - and have continued to decline, such that there are now less than 100 per month compared to over 1,200 per month just 3 years ago.
The LAPD updated its policy on pretext stops in spring 2022, requiring officers to state the reason they believe a more serious crime is at play to their body camera before approaching the vehicle for a pretext stop. Traffic stops for minor violations dropped 40% almost overnight.
If Los Angeles can nearly cut pretext stops in half without banning the stops altogether, then is a ban necessary?
We shouldn’t ban police from enforcing the law
The idea of banning law enforcement officers from enforcing the law feels like the definition of an oxymoron. More importantly, banning police from enforcing select laws could cause confusion on the behalf of both officers and residents - and erode confidence and respect for the broader set of laws currently on the books.
In the debate surrounding San Francisco’s decision to ban pretext stops for 9 traffic violations, San Francisco Police Chief Bill Scott made this argument:
"Prohibiting enforcement of the law I have a fundamental disagreement with that. What's in the best interest of the city? We have to address disparities. Of course, we do. We have to take care of public safety. Of course, we do. Let's find a balance."
Mayor London Breed, who supports reducing pretext stops, agrees with Chief Scott that a ban, particularly from the Police Commission, is not the right way to achieve the end goal:
“Breed said it is the job of the legislature, not an un-elected commission, to change traffic laws, and that the proposal would cause confusion for officers and safety risks for citizens.”
Her spokesperson went further:
“Injury and death is the worst case, but if we don’t enforce traffic laws, there’s no reason for people to follow them. Enforcement is about deterrence too.”
Rather than telling police not to enforce existing law, supporters of reducing or ending pretext stops could pursue legislative action to change the law - which may happen this year.
My Assessment
It seems quite clear that pretext stops are racially biased, the racial bias is not leading to higher discovery rates of evidence of more serious crimes, and traffic stops, in general, have a negative effect on all people experiencing them. As a result, we should try to limit pretext stops if they have an insignificant or positive effect on traffic safety and crime.
It does seem possible to ban stops for certain violations without impacting traffic safety. This places significant importance on identifying the right violations to ban and then, continuing to monitor relevant data to see if the relationship between certain violations and traffic safety changes.
When it comes to the relationship between pretext stops and crime, I am definitely skeptical of Los Angeles Police Commission President William Briggs’ claim that no one could find data that shows pretext stops reduce violent crime, especially given the results of the 2023 meta-analysis cited earlier. The Nashville example, which is being lauded as a victory for pretext stop bans, presents a conflicted message, if not a warning of what could happen when traffic stops decline by 90%. While it’s too early to tell what will happen in Los Angeles, after pretext stops dropped dramatically this spring, violent crime was up 1% and property crime was up 10% from 2021. These correlations don’t prove anything, but they offer reason for caution.
Despite this caution, at a 2-3% arrest rate, pretext stops don’t seem to be a particularly effective or efficient tool for reducing crime. As a result, I would look for ways to reduce pretext stops without banning them in order to reduce racial bias in policing and to redirect officer time elsewhere - even if it only is 51 minutes per year per officer.
The LAPD's new policy - which allows pretext stops, but requires officers to explain on their body camera why they believe the stop will lead to evidence of a more serious offense before approaching a vehicle - seems to be the most sensical way to achieve this. The policy has resulted in a significant reduction in pretext stops, a reduction in racial disparities in traffic stops, and a slight increase in the rate of discovery of contraband or other evidence.
Beyond those early results, it makes sense to allow officers to enforce existing laws, but to incentivize them to make better decisions about when to take the time to enforce laws. LAPD Sergeant William Batista says it well:
“What we’re doing is we’re explaining ourselves more and identifying the reasoning behind it, instead of, ‘Well, I just had a hunch. I saw the guy and he looked like he might have been doing something. He gave me that look.’ That’s not enough. We got to make sure that we’re appropriately criminally profiling. We don’t do racial profiling. We do criminal profiling.”
While LAPD’s policy seems most advantageous now, the state should consider waiting for 1-2 years before implementing a statewide policy. Recent policy changes in Los Angeles, San Francisco, and a number of other Californian cities offer a helpful laboratory to evaluate the impact of reducing pretext stops. We’d be wise to wait and learn from them before making any changes.