Descriptive analysis of reports on autonomous vehicle collisions in California: January 2021–June 2022




autonomous vehicles, collisions, disengagements, safety


The characteristics of autonomous vehicles’ collisions from 2021 and the first half of 2022 in California confirm trends reported in previous years. Driving in autonomous mode was associated with fewer instances in which the AV was deemed to be at fault in a collision. Most collisions in autonomous mode were rear-end collisions at intersections. Single vehicle collisions occurred mostly in manual mode. Collisions with vulnerable road users occurred mostly while the autonomous vehicle was in manual mode, often right after disengagement from autonomous mode. In collisions with other vehicles that occurred after disengagement, the other vehicles were frequently deemed to be at fault. Compared to 2021, the collision reports from the first half of 2022 indicate higher shares of collisions in autonomous mode, rear-end collisions, and collisions with vulnerable road users.


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Author Biographies

Petr Pokorny, Institute of Transport Economics, Norway

Petr Pokorny is a traffic safety researcher at the Institute of Transport Economics in Norway. He has a Doctoral degree from the Norwegian University of Science and Technology (NTNU, Trondheim). His current research focuses on video observations of encounters between automated shuttles and other traffic participants and on evaluation of bicycle infrastructure measures.

CRediT contribution: Conceptualization, Data curation, Methodology, Formal analysis, Writing—original draft.

Alena Høye, Institute of Transport Economics, Norway

Alena Katharina Høye is a traffic safety researcher at the Institute of Transport Economics in Norway. She has a Doctoral degree from the University of Mannheim, Germany. Her research interest is in road safety area with a focus on infrastructure design and safety inspections, as well as meta-analysis and crash modelling.

CRedit contribution: Formal analysis, Writing—review & editing.


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How to Cite

Pokorny, P., & Høye, A. (2022). Descriptive analysis of reports on autonomous vehicle collisions in California: January 2021–June 2022. Traffic Safety Research, 2, 000011.



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