Objective Medical accidents have resulted in actual harm for patients, been costly for health care system, and diminished trust for both patients and practitioners. The present study analyzed malpractice claims related to accidents in psychiatric inpatient units. Methods This study analyzed defendants, cases and plaintiffs or patients characteristics, degrees of injury, and types of accidents in 85 civil malpractice suits filed from 2005 to 2015 with a focus on the methods and locations of suicides. Results Most defendants were psychiatrists (n=43). Of the 85 cases, 56 (65.9%) were decided in favor of the plaintiff, most commonly on the grounds of negligence and violation of sound facility management principles. The most common diagnosis of patients was schizophrenia (n=31). The damages were deaths in 52 cases and injuries or other damages in the remaining 33 cases. The most common accident was suicide (n=28), followed by escape attempts (n=15). The most common suicide method was hanging (n=21), which was usually committed in the private room using objects like door handles. Conclusion To reduce medical accidents, medical staff should monitor high-risk patients closely and constantly. Sufficient numbers of well-trained personnel are required to meet this standard. Reducing environmental hazards such as removing anchor points and installing door locking systems will improve patient safety.