On March 3, 2025, the Study Group on Measures to Ensure Safety Performance of Automated Vehicles (the “Study Group”) established under the Automated Driving Working Group of the Ministry of Land, Infrastructure, Transport and Tourism (the “MLIT”), published its final report¹ (the “Report”). The Report outlines Japan’s approach to (i) the further revision of the existing Safety Standards² and Guidelines³ for automated vehicles (“AV”s) and (ii) the framework for ensuring compliance with such revised Safety Standards and Guidelines. Key points include, for (i), scenario-based tests that require AVs to demonstrate a level of safety exceeding that of a “competent and careful human driver” in a variety of scenarios, and for (ii), In-Service Monitoring and Reporting (“ISMR”) by the manufacturer, as well as supervision by regulatory agencies, after market launch.

This Newsletter provides an overview of key aspects of the Report, highlights anticipated legislative changes, and offers guidance to stakeholders who are preparing for the deployment of automated vehicles in Japan.

(1)　Legal Developments regarding the Specification of Safety Standards and Guidelines

The Road Transport Vehicles Act (the “RTVA”), which lays down relevant safety standards, was amended in May 2019 to subject level 3 and 4 automated driving systems (“ADS”) to the Safety Standards, as well as specify the relevant safety standards to be applied. Furthermore, in June 2024, new guidelines were formulated to clarify the concept of safety assurance and the socially acceptable safety level for level 4 AVs used for passenger or goods transport services.

(2)　Japan’s Safety Assessment Project for ADSs

Since 2018, under the Mobility DX Working Group, Japan has been promoting the SAKURA Project, which is deliberating on the generation of scenario patterns and evaluation methods to test whether ADSs can adequately respond to the various scenarios, specifically confirmation methods to determine whether ADSs can secure a safety level equivalent to or higher than a that of a “competent and careful human driver” under a variety of scenarios.  

(3)　International Trends in Safety Standards for AVs

International safety standards for automated driving are being developed through the World Forum for Harmonization of Vehicle Regulations (WP.29), in which Japan actively participates. International discussions to establish legally binding standards for AVs, including level 4 AVs, by June 2026 are currently underway.

Although, since the 2019 amendment of the RTVA, there had been advancements on the legal framework to ensure AVs’ safety, the Report points out the need to set out additional safety requirements for AVs under the following approaches to promote the safer development and adoption of AVs.
 

• Basic Policy
   

The Report plans to first revise the Guidelines while taking into account global trends and ensuring that manufacturers and operators are not discouraged from technological development and innovation. Specifically, the Report advocates for developing, based on existing domestic research, a scenario-based safety assessment approach and clarifying safety requirements regarding “competent and careful human driver”, as well as, in view of the anticipated adoption of driverless vehicles, updating Japan’s Safety Standards to accommodate AVs ahead of the world. Furthermore, Japan intends to propose Japanese safety evaluation methods and AV specific safety standards developed based on policies set out in the Report at WP.29 and other international venues so they could be reflected in international discussions.
 

• Approach to the Revision of Guidelines
   

The general approach to ensuring safety is based on the following approach identified in the “Report of the Sub-Working Group on the Examination of Social Rules Concerning Automated Vehicles in the AI Era” dated June 2024 (the “SWG Report”), taking into account the fact that AVs are required to completely comply with traffic regulations under international standards and guidelines. 

a.    AVs must comply with the Road Traffic Act (the “RTA”).⁴ 
b.    AVs must not cause accidents as long as other road users comply with the RTA.
c.    Even when other road users do not comply with the RTA, AVs must avoid accidents to the greatest extent possible. 
d.    If an accident is unavoidable due to non-compliance by other road users, AVs must strive to mitigate damage to the greatest extent possible.

The safety evaluation method demonstrates a scenario-based approach to systematically organize scenarios which AVs may encounter and evaluate whether the ADSs have the necessary capabilities to address such scenarios, and, similar to UN documents, classifies them into: (i) Nominal Scenarios, which involve normal traffic conditions, (ii) Critical Scenarios, which involve the risk of collision, and (iii) Failure Scenarios, which involve malfunctions.

With regard to safety evaluations for individual vehicles, manufacturers must, for each specified risk scenario, first define test parameters for performance evaluation and create scenario-based test cases, and then confirm performance evaluation and compliance through simulation, test track, and on-road testing. 

For each scenario test case to evaluate AV performance, it is expected that, based on the general approach to ensuring safety, the evaluation benchmark will involve assessing whether the AV exceeds the level of safety achieved by a “competent and careful human driver”. The manufacturer must demonstrate to government and evaluation agencies that the AV fulfills the foregoing evaluation benchmark in specific scenarios. At the same time, the government will continue to fine-tune or formulate these safety requirements using data resulting from driver experiment and other methods.
 

• Review of Safety Standards for Driverless Vehicles
   

The Report also proposes specific revisions to the Safety Standards to accommodate driverless vehicles, such as eliminating the Safety Standards for rearview mirrors, which will no longer be necessary for driverless vehicles.

• Approach to Ensure Compliance with Revised Safety Standards
   

Since revisions to the Safety Standards significantly impact vehicle users and manufacturers, the Report adopted the following framework:

(i)    New vehicles must comply with the revised standards, after a transition period; and
(ii)    For in-use vehicles, conformity shall be determined on a case-by-case basis, considering the degree of safety criticality and technical difficulty of each revision.
 

• Continuous Safety Improvements by Manufacturers and Authorities  
   

With regard to compliance with the Safety Standards by ADSs, the Report emphasizes the importance of ongoing ISMR by manufacturers to maintain safety even after market launch.

If malfunctions or significant unforeseen safety issues are identified, manufacturers must analyze the causes, assess the impacts, and consider necessary corrective measures for in-use vehicles. The authorities, based on reports by the manufacturer and other relevant organizations, must assess the need for further revisions to the Safety Standards, and provide guidance to manufacturers to ensure proper improvements as needed.

The Report accelerates Japan’s efforts to provide the ideal regulatory environment for the further adoption of AVs. Stakeholders should closely monitor ongoing legislative developments and prepare for the introduction of scenario-based safety evaluation requirements with the benchmark of a “competent and capable human driver”, as well as further ISMR efforts by manufacturers to ensure and enhance safety after market launch. Mori Hamada will continue to provide updates and legal analysis as these reforms progress⁠.