AUGUST 2020 | FHWA-SA-20-031

ZERO DEATHS SUCCESS STORY — PARTNERSHIPS

Zero Traffic Fatalities Task Force and Speed 

Limit Setting Report — California

Background 

Motor vehicle collisions are a leading cause of 

unintentional injuries and deaths among all age 

groups in the United States. In 2017, approximately 

3,600 deaths and over 14,000 serious injuries 

occurred as a result of traffic collisions in 

California, costing the State over $53.5 billion. 

Twenty-six percent of the collisions were speedingrelated, which included vehicle speeds that were 

unsafe for conditions or in excess of the speed 

limit. 

This spurred the legislature into action and in 

2018, the California Assembly signed Assembly 

Bill 2363. This Bill required the establishment of a 

Zero Traffic Fatalities Task Force. The Task Force 

aimed to evaluate the ways in which speed limits 

are set in California, suggested alternatives to the 

current speed-limit-setting process (85th-percentile 

method1), and proposed policies to reduce traffic 

fatalities to zero. AB 2363 directed the California 

Secretary of Transportation to publish a Report of 

Findings following the conclusion of the Task Force 

activities and submit it to the Legislature.

Implementation

The 24 stakeholders selected for the Task Force 

represented diverse constituencies, from State 

and local agencies, bicycle and pedestrian 

safety organizations, academic institutions, 

transportation safety advocates, labor 

organizations, and other experts. The creation of 

1 85th-percentile speed is the speed at which 85 percent of 

free-flowing traffic is traveling at or below.

Key Successes

The efforts of the California State 

Transportation Agency and its partners 

to form a Zero Traffic Fatalities 

Task Force led to these partnership 

successes:

Recruited numerous stakeholders 

to comprise the Task Force and Advisory 

Group from a diverse set 

of agencies and organizations.

Held Task Force meetings and an 

Advisory Group meeting to discuss and 

develop innovative ways to increase 

safety on California’s roadways. 

The solutions and ideas developed 

during these productive sessions were 

incorporated into the final Report of 

Findings that was delivered to the 

Legislature.

Developed a report of speed limit setting 

findings which was submitted to the 

California Legislature in January 2020.
an Advisory Group, made up of interested parties 

who are not members of the Task Force, helped 

to inform and advise Task Force members on 

traffic safety issues. 

The Task Force held three day-long workshops 

like the one shown in figure 1. These workshops 

included presentations and discussions on the 

contributing factors to speed-related crashes in 

the State; enforcement, education, and policy 

strategies to manage speed; and current and 

emerging methodologies to set speed limits. The 

agendas and presentations from each meeting 

are available online: https://calsta.ca.gov/

subject-areas/enforcement-and-safety/zerotraffic-fatalities. Lastly, the University of California 

Institute of Transportation Studies completed a 

Research Synthesis that helped inform the Report 

of Findings (figure 2). 

Outcomes 

The California State Transportation Agency 

published its Report of Findings in January 2020. 

As directed by AB 2363, the Report of Findings 

addressed a number of topics, including existing 

and alternative speed limit setting processes, 

policies on local road speed reduction, roadway 

engineering recommendations, and other 

approaches to improving traffic safety and 

eliminating fatalities.

The report explained the history and 

assumptions behind the existing 85th-percentile 

methodology and the extent of its use across 

local, State, national, and international levels. In 

some countries, speed limits are based on the 

human body’s tolerance to withstand impact 

forces from crash types likely to occur rather 

than the 85th-percentile speed. The report also 

found that the 85th-percentile methodology 

is also related to speed creep, driving up the 

speed limits on the roadway over time. The 

report recommends the development and 

implementation of a new roadway-based 

context sensitive approach to establish speed 

limits that prioritizes the safety of all road users.

The report discussed additional steps to reduce 

pedestrian and bicycle crashes and the overall 

number of fatalities. These included engineering 

countermeasures (curb extensions, chicanes, 

chokers, median islands, raised crosswalks, 

roundabouts), enforcement countermeasures, 

and educational countermeasures. The report 

also noted that local bicycle and pedestrian 

plans do not have an impact on the posted 

speed limit calculation unless they change an 

aspect of the roadway, such as traffic calming 

interventions, post-implementation.

Figure 1. Photograph. A meeting of the California Zero Fatalities Task Force. 

© 2019 Caltrans
There are eight overarching themes in the 

California State Transportation Agency’s 

Report of Findings:

1. Revise the procedure for setting speed limits 

to allow more flexibility for urban versus 

rural areas, the ability of agencies to adjust 

the limit via deviations, and traffic survey 

requirements.

2. Add more options for lower accepted 

unposted speed limit locations, specifically 

for business activity districts and school 

zones, to increase crash survivability for 

vulnerable users.

3. Review allocations of Highway Safety 

Improvement Program funds to contribute 

to the installation of engineering 

countermeasures.

4. Revise, consolidate, and clarify all 

documentation, resources, and 

guidance related to speed limit settings 

and highway design.

5. Develop and maintain a State safety 

monitoring program to identify and 

address crash locations related to speed 

and vulnerable users.

6. Investigate the role and impact of the Level of 

Service requirement for corridor improvements 

and be involved in the migration to vehicle 

miles traveled-based standards.

7. Consider a range of complex policy issues 

and engage impacted communities in 

the development of guidelines related to 

automated speed enforcement.

8. Develop a Statewide coordinated traffic 

safety campaign.

Ultimately, the Report of Findings represented 

the culmination of an extensive effort that 

brought diverse stakeholders from across the 

State. As the California State Transportation 

Agency and its departments implement the 

Report’s recommendations, it will draw on 

the Task Force’s technical expertise in order 

to achieve the goal of making the State’s 

roadways safer for all Californians.

Funding

The State of California funded the Zero Traffic 

Fatalities Task Force. 

Figure 2. Graphic. Timeline for the actions of the Zero Traffic Fatalities Task Force.2

© 2020 CalSTA

2 CalSTA. (2020). CalSTA Report of Findings AB 2363 

Zero Traffic Fatalities Task Force. CalSTA. https://calsta.

ca.gov/-/media/calsta-media/documents/calsta-report-of-findings-ab-2363-zero-traffic-fatalities-task-force-a11y.pdf. Last 

accessed on February 12, 2020.

POINT OF CONTACT

RACHEL CARPENTER

CHIEF SAFETY OFFICER

CALIFORNIA DEPARTMENT OF TRANSPORTATION

RACHEL.CARPENTER@DOT.CA.GOV