# Medical Accident Investigation System of Japan in Malpractice Litigation: A Non-Punitive Reporting System?

## TL;DR

This study examines how Japan's medical accident reports are used in malpractice lawsuits, revealing a mismatch with the system's intended non-punitive purpose.

## Contribution

The paper highlights discrepancies in Japan's medical accident reporting system's use in litigation versus its non-punitive design.

## Key findings

- 13 cases and 15 reports were analyzed, showing reports are often used as evidence of negligence.
- Most reports (80%) were submitted by bereaved families, and 60% were cited as evidence in judgments.
- Three reports directly provided grounds for establishing negligence in court.

## Abstract

The investigation and reporting of medical accidents are important to prevent medical errors and ensure patient safety. A successful reporting system should be non-punitive, meaning that reporters are free from any reprisals that arise owing to their reporting of a medical incident.

In this study, we reviewed all lawsuits involving reports in Japan’s Medical Accident Investigation System, identified using a Japanese database of lawsuits (https://www.westlawjapan.com/). We examined the basic characteristics of medical accident cases and how these reports were cited in judgments in medical malpractice litigation.

A total of 13 cases, including 15 reports, were collected in this study. Two judgments cited two kinds of reports: those conducted in-hospital and reports prepared by the Medical Accident Investigation and Support Center. Twelve reports (80.0%) were provided by the bereaved family, and four reports (26.7%) were entered into evidence as exhibits for the determination of negligence. Nine reports (60.0%) were cited as evidence of negligence; among these, six reports included content establishing negligence among medical professionals. At least three reports provided grounds for the establishment of negligence in the judgment.

We described the basic characteristics of malpractice lawsuits related to the medical accident reporting system established under Japanese law. The current situation of reports provided in medical malpractice lawsuits in Japan indicates discrepancies between their use and the purpose of a non-punitive reporting system. Systems to ensure patient safety should be separate and distinct from those intended to report negligence by medical professionals.