Understanding and resolving deadlock situations: Drivers' perception, rule application and behavior at T-intersections

Intersections are critical points for traffic accidents, often resulting from drivers' failure to correctly apply right-of-way rules. A particular challenge arises in deadlock situations, where the right-of-way is not clearly regulated. This study investigates how accurately drivers perceive deadlock situations at T-intersections and how these perceptions influence their behavior. Participants watched videos from a driver's perspective showing approaches to a T-intersection from all three directions, where two other vehicles arrive simultaneously, creating an unresolved deadlock. After each video, participants reported their intended behavior. Additionally, they were asked to either identify the vehicles' travel direction, anticipate their behavior or determine the right-of-way. The results show that most drivers fail to correctly identify the right-of-way, often misattributing priority to one vehicle. This likely stems from applying only one of the two relevant right-of-way rules, leading to priority being assigned primarily to the vehicle approaching from the right. Drivers also assigned right-of-way more frequently to an approach direction when they were not approaching from that direction themselves. The approach direction and assumed priority further influenced how drivers anticipated the behavior of the other vehicles and how these expectations shaped their own behavior. The two relevant vehicles were not equally attended to, leading also to errors in detecting their intended trajectories. Overall, drivers do not appear to consider all relevant information, resulting in an inaccurate representation of the situation, and their behavior can only be interpreted in relation to their approach direction. Based on the findings recommendations for autonomous vehicles are given. • A majority of drivers fail to correctly identify the right-of-way in deadlocks. • Drivers often apply only one of the two relevant right-of-way rules. • Misunderstanding of priority rules influences drivers' behavior in deadlocks. • Approach direction and perceived priority shapes expectations of others' behavior. • It also affects the identification other vehicles' travel direction.