Objectives The purpose of this study was to compare the demographic, clinical, and criminal characteristics and legal judgments of criminal cases, in which psychiatric evaluation was requested, and to identify factors affecting criminal responsibility judgments. Methods The medical records of 100 subjects that committed crimes and the judgment records of 51 subjects admitted to Yongin Mental Hospital from February 2005 to February 2021 were analyzed retrospectively. Psychiatric disorder groups were compared with respect to demographic, clinical, criminal characteristics, and legal judgments. Factors affecting criminal responsibility judgments were identified by comparing legal judgment groups. Results Psychiatric history, criminal motivation, and criminal history differed significantly between psychiatric disorder groups. Differences between the opinions of the appraiser and courts regarding criminal responsibility were significantly dependent on psychiatric disorder type, and there was a consistent tendency according to the psychiatric disorders, but there was a difference of opinion between the two groups. Conclusion The findings of the current study suggest psychiatric diagnoses and symptoms such as psychotic symptoms and cognitive impairments that provoke crime can influence criminal responsibility judgments.