Pedestrian deaths have become an increasingly large share of the traffic fatality burden of the United States. After three decades of decline, pedestrian fatalities rose by more than 40 percent between 2009 and 2016, a reversal that placed pedestrians among the fastest-growing categories of road user deaths.(1) The upward movement continued through the following years, and by the early 2020s pedestrians represented a share of motor vehicle deaths that had not been observed in the previous four decades.(2) The United States also diverged from other high-income countries, where pedestrian fatality rates kept falling while the American rate climbed.(3) Across high-income countries, walking safety improved more in Europe than in the United States, where per capita fatality rates remained higher.(4) This reversal is not a single-year anomaly; it reflects a sustained change in the conditions under which pedestrians are killed, and it has turned pedestrian safety into a central concern for transport and public health policy. Although each factor has been studied separately, the recent national increase has rarely been decomposed into the contributions of light condition, road class and vehicle type.

Darkness is the condition most consistently associated with pedestrian death. Most fatal pedestrian crashes in the United States occur at night, and the growth of pedestrian fatalities since 2009 has been faster in darkness than in daylight.(5) Nighttime deaths have been linked to roadway infrastructure, user behavior and situational factors that interact with reduced visibility.(6) Lighting levels and their photometric criteria have been modeled as determinants of nighttime pedestrian crash risk on roadway segments.(7) Analyses across the injury severity spectrum also show that lighting condition distinguishes fatal from nonfatal outcomes.(8) The temporal pattern of darkness is therefore a plausible candidate to explain part of the recent increase, yet the magnitude of its contribution has not been separated from the contribution of other factors, and it is not known whether the nighttime share of deaths simply accompanies a general rise or grows faster than the daytime share. The recent increase has accordingly been described as a nighttime phenomenon, but whether darkness explains a disproportionate share of the growth has not been quantified against the other candidate factors.

The roadway environment concentrates pedestrian deaths on specific classes of roads. Pedestrian fatal crashes in the United States cluster at a small number of locations, many of them along major roads that combine high speeds with frequent crossing demand.(9) Highways and the neighborhoods around them have also been associated with pedestrian deaths in ways that extend beyond the roadway itself.(10) Arterial roads, which carry large volumes at speeds above those of local streets, are repeatedly identified in crash analyses, but their contribution to the observed time trend, as opposed to their share of the total, remains unclear. Understanding whether the growth concentrated on these roads, rather than spreading evenly across the network, has direct consequences for where safety investment should be directed. A trend concentrated on arterials would point toward speed and road design, whereas a trend spread across all road classes would point toward broader changes in walking and travel behavior.

The type of vehicle that strikes a pedestrian modifies the risk of death. Light trucks and sport utility vehicles have long been associated with higher pedestrian injury severity and mortality than passenger cars.(11-13) Recent work confirms that large vehicles increase the severity of pedestrian and pedalcyclist injuries,(14) and state-level analyses associate light truck and sport utility vehicle exposure with pedestrian deaths.(15) The American vehicle fleet has also shifted toward utility vehicles over the past decade, which raises the question of whether that shift contributed a disproportionate share of the recent increase in pedestrian fatalities. If so, vehicle-focused countermeasures would be warranted; if not, the increase would more plausibly reside in the road environment and in exposure.

The aim of this study was to quantify trends in pedestrian fatalities in the United States between 2013 and 2021 and to estimate the contribution of light condition, roadway class and vehicle type to the observed change. Four hypotheses were derived and tested. H1 stated that pedestrian fatalities increased between 2013 and 2021. H2 stated that the increase was disproportionately concentrated in darkness. H3 stated that the increase was disproportionately concentrated on arterial roadways. H4 stated that the increase was disproportionately concentrated in crashes involving light trucks and sport utility vehicles.

Between 2013 and 2021, FARS recorded 54,019 pedestrian fatalities in the United States (Table 1). Males accounted for 69.8% of the fatalities, and the median age was 48 years (IQR 32-61).

Darkness was recorded in 74.6% of the fatalities. Principal and minor arterials accounted for 61.3% of the fatalities, light trucks or sport utility vehicles for 40.8%, and passenger cars for 41.3%. The annual series rose in most years, with a plateau between 2017 and 2019 and a steeper increase from 2020 to 2021 (Figure 1).

Within each classification the high-risk stratum was the largest single category: darkness exceeded daylight or twilight, arterials exceeded any other road class, and light trucks or sport utility vehicles were close to passenger cars.

The increase in pedestrian fatalities in the United States between 2013 and 2021 was not distributed evenly across conditions, roads and vehicles. Darkness and arterial roadways accounted for the entire growth, with the latter exceeding the total because non-arterial deaths fell, while light trucks and sport utility vehicles rose in parallel with passenger cars. These findings place the recent worsening of pedestrian safety in two specific environments rather than across the road system as a whole, and they redirect attention from the vehicle fleet toward visibility and road design. Most previous national work has described either the level of each risk factor or the aggregate trend, and the decomposition offered here connects the two.

The overall upward trend is consistent with earlier national analyses. Pedestrian deaths rose after 2009 at a rate that reversed decades of progress,(1) and the divergence from peer countries persisted through the study period.(3) The annual increase estimated here is similar in direction to joinpoint analyses of motor vehicle fatalities, which identified a turning point in the early 2010s.(19) The most recent preliminary data indicate that the rise continued after 2021,(2) so the pattern described here is not confined to the years examined. The consistency across independent sources suggests that the trend reflects structural conditions rather than a temporary fluctuation, which makes the identification of its specific components all the more relevant for policy. The steadiness of the annual increase across the period likewise indicates a persistent pressure rather than an isolated spike. The present analysis adds to that literature by quantifying how the increase was distributed across the three candidate factors.

The concentration of the increase in darkness extends previous work on nighttime risk. Nighttime pedestrian fatalities have been examined across infrastructure, user, vehicle and situational factors, and darkness emerges as a dominant condition.(6) Analyses across the injury severity spectrum show that lighting condition distinguishes more severe outcomes,(8) and reviews of darkness-specific evidence conclude that the nighttime share of pedestrian deaths has grown.(5) The faster trend in darkness estimated here is consistent with those observations and suggests that visibility, rather than exposure alone, shapes the time course of the epidemic. Roadway lighting photometric criteria also modulate nighttime crash risk,(7) and visibility factors have been linked to injury severity in disaggregated crash data.(20) Spatial studies add that nighttime pedestrian safety varies with land use and alcohol environments,(21) which may help explain where darkness-related deaths concentrate. In line with those findings, the present estimate shows that darkness absorbed most of the increase while the daylight and twilight count barely moved, a pattern difficult to reconcile with a purely exposure-driven explanation. The finding that even the daylight and twilight count increased, although slowly, indicates that darkness does not account for the entire phenomenon, only for most of it. The similar size of the dark-lighted and dark-not lighted categories also suggests that existing lighting did not fully offset the risk associated with darkness.

The finding on arterial roadways is consistent with the geography of pedestrian crashes. Fatal pedestrian crashes in the United States cluster at a limited set of locations, many on major roads that combine high traffic volumes with crossing demand.(9) Highways and the neighborhoods around them are associated with pedestrian deaths, particularly where the road separates communities or concentrates activity.(10) The present result adds a temporal dimension: the growth was located on arterials and was driven by them, while deaths on other classes of road did not increase. This pattern is consistent with the stability of factors that influence injury severity along roads(22) and with nighttime crash pattern analyses that identify differences between segments and intersections.(23) Roads engineered for through movement may therefore have amplified the broader forces that raised pedestrian deaths, a possibility reinforced by the observation that non-arterial deaths actually fell. The decline in non-arterial deaths, although not statistically significant on its own, suggests that the forces raising fatalities were offset on slower roads.

The result for light trucks and sport utility vehicles was contrary to expectations in its trend component, although it did not contradict the established severity evidence. Earlier studies showed that light truck vehicles carry a higher mortality risk per pedestrian struck than passenger cars,(11) that fatality rates per exposure differ by vehicle type,(12) and that large sport utility vehicles kill a higher proportion of the pedestrians they strike.(13) More recent analyses confirm that large vehicles increase injury severity(14) and that state-level fatality counts track light truck and sport utility vehicle exposure.(15) The present analysis found no differential trend between the two groups, which implies that the growth in deaths involving light trucks and sport utility vehicles was proportional to the growth involving passenger cars. The finding does not negate the higher per-crash risk; it indicates that the increase over time was not preferentially attributable to these vehicles. Fleet composition, which has shifted toward utility vehicles, and vehicle design features that affect pedestrian kinematics(24) remain relevant, but their role in the trend is shared with the general growth of traffic.(25) Impact speed also modulates severity independently of vehicle type,(26) which reinforces the importance of the road and lighting conditions reported here. The rejection of this hypothesis therefore sharpens, rather than weakens, the case for environment-focused intervention. A more complete test would require fleet registration data over the same period to separate changes in exposure from changes in risk per vehicle, because the present analysis compared trends in counts rather than rates per registered vehicle.

Several mechanisms may link darkness and arterial roadways to the observed increase. Reduced visibility at night shortens the time available for drivers to react and raises effective impact speeds, and the same road that is forgiving for motorized traffic by day becomes less so after dark. Arterial corridors combine higher design speeds with frequent crossing demand, a pairing that multiplies the probability of a fatal outcome when a crash occurs. Substance use is also associated with pedestrian fatalities,(27,28) and it is more prevalent in nighttime crashes, where it may interact with poor lighting. The growth in pedestrian deaths has likewise coincided with changes in travel patterns that place more walking in darkness and on high-volume roads, including longer commutes and a shift of pedestrian activity toward the early evening. Changes in the timing of walking relative to daylight could further concentrate exposure in darkness, but exposure data were not available to test this directly.

Countermeasure evidence supports the priority assigned to lighting and road design. Lighting improvements are among the measures proposed to reduce the nighttime burden, and the evidence on darkness emphasizes both roadway illumination and the design of crossings where pedestrians are visible after dark.(5,7) Speed reduction is equally relevant, because the probability of death rises steeply with impact speed regardless of the vehicle involved.(26) Crossing treatments that shorten the distance a pedestrian is exposed to traffic, such as medians and marked crossings with adequate illumination, address the same visibility problem at the points where pedestrians interact with arterial traffic. The combination of slower speeds and better illumination on arterials addresses the two strata that absorbed the increase estimated here, and it is consistent with a Safe System perspective in which the road environment compensates for human error and limited visibility.

Social and structural factors shape where these risks fall. Disparities in traffic fatalities by race and ethnicity are documented,(29) pedestrian fatalities differ markedly by race,(30) and historical redlining is associated with contemporary pedestrian deaths.(31) These patterns suggest that the trends described here are a matter of visibility and road geometry and of who is exposed to those conditions. Neighborhoods that were historically disinvested often lie along arterial roads and receive less lighting investment, which could place their residents where the two risk factors identified here converge. These intersections suggest that the two strata identified here, darkness and arterials, are not randomly distributed across the population. Addressing the trend therefore requires attention to both the physical environment and the social geography of exposure. Trends in walking safety in high-income countries further indicate that the American outcome is not inevitable,(4) because peer countries with different road and lighting standards did not experience the same rise.

The strengths of this study include the use of a complete national census of fatal crashes rather than a sample, the standardized coding of light condition, road class and vehicle type across nine years, and the decomposition of the increase into the shares attributable to each factor. The analysis separates trend from level, which avoids attributing the increase to a factor merely because that factor is common. The use of a single data source with consistent definitions also avoided the comparability problems that arise when records from different agencies are combined. The explicit formulation and resolution of hypotheses kept the interpretation tied to the evidence rather than to the descriptive prominence of each risk factor, and the robustness of the total trend to the exclusion of 2020 indicates that the pandemic did not produce the observed pattern.

The decomposition of the increase into shares deserves a methodological caveat. The shares are descriptive quantities computed from two endpoints, and they can exceed 100 percent when the complementary stratum declines, as occurred for arterial roadways. They should be read as accounting statements of where the change occurred rather than as causal attributions, and the regression-based interaction estimates provide the corresponding inferential test. The two approaches agreed: darkness and arterial roadways showed both large shares and significant differential trends, while the vehicle contrast showed neither.

Pedestrian fatalities in the United States increased steadily between 2013 and 2021, and the annual change remained similar when the pandemic year was excluded. The increase was concentrated in darkness, which absorbed most of the growth, and on arterial roadways, where the rise exceeded the total because non-arterial fatalities declined. The contribution of light trucks and sport utility vehicles to the increase did not differ from that of passenger cars. The findings locate the recent worsening of pedestrian safety in the night and on major roads rather than in the changing vehicle fleet, and they favor interventions in the road environment over a focus on the vehicle fleet alone.