California recorded nearly 4,000 traffic fatalities in 2024.
But according to new research, those deaths are not spread evenly across the state. Instead, they are heavily concentrated within a relatively small number of counties, during specific hours of the day and around a handful of predictable risk factors.
The findings raise an important question for policymakers, transportation planners and local governments: if traffic fatalities are increasingly predictable, should road safety resources be deployed differently?
Researchers at Omega Law Group analyzed California traffic fatality data and found that just ten counties accounted for approximately 69% of all traffic deaths statewide.
Los Angeles County alone recorded 744 fatalities, nearly one in five traffic deaths across California. San Bernardino, San Diego and Riverside counties followed closely behind, creating a concentrated corridor of roadway risk across some of the state’s busiest transportation networks.
The Geography of Risk
For decades, transportation safety has often been approached through statewide campaigns and broad public awareness initiatives.
However, the data suggests a more targeted strategy may be warranted.
While California has 58 counties, the vast majority of fatalities occur within a much smaller group of high-risk regions. These counties share several characteristics: large populations, extensive freeway systems, significant commuter traffic and growing logistics networks.
The concentration raises broader questions about whether road safety investments should be distributed equally or directed toward locations where the risk is greatest.
A Three-Hour Window Produces Disproportionate Losses
The study also found that California’s deadliest driving period occurs between 9 p.m. and midnight.
During that three-hour window, 299 fatalities were recorded in 2024, making it the most dangerous period on California roads. The figure was more than three times higher than the safest part of the day, between 9 a.m. and noon.
Researchers point to a combination of factors driving the trend, including reduced visibility, alcohol impairment, speeding and fatigue.
For transportation agencies, the finding highlights how a relatively narrow time period accounts for a disproportionate share of roadway deaths.
The Cost of Preventable Behavior
The analysis identified speeding and alcohol impairment as the two largest contributors to fatal crashes.
Speeding was linked to 965 deaths in 2024, while alcohol impairment contributed to 943 fatalities. Together, the two behaviors accounted for more than half of all traffic deaths statewide.
Seatbelt non-use was also associated with hundreds of fatalities despite decades of public awareness campaigns and well-established evidence regarding seatbelt effectiveness.
From a public policy perspective, the findings suggest that many of California’s most deadly roadway risks are not infrastructure failures but behavioral ones.
A Resource Allocation Problem
California continues to invest heavily in transportation infrastructure, safety initiatives and enforcement programs.
Yet the latest data suggests that road safety challenges may increasingly be a matter of precision rather than scale.
If a majority of fatalities occur within a limited number of counties, during a limited number of hours and from a limited number of risk factors, policymakers may have an opportunity to concentrate interventions where they are most likely to have an impact.
That could include:
- targeted DUI enforcement
- late-night patrol deployment
- improved roadway lighting
- pedestrian safety improvements
- focused infrastructure investment in high-risk corridors
As California continues to confront rising transportation demands, the challenge may no longer be identifying where the risks exist.
The data already does that.
The challenge is determining how effectively resources are deployed to address them.