The relationship between mental illness and violent behavior is a complex phenomenon. Scientific literature indicates that the presence of a mental disorder, even severe, is not sufficient, alone, to predict or motivate violent behavior, which seems to be more associated with other intermediate variables. The phenomenon of psychiatrization of violent behavior can be defined, from a psychiatric-forensic point of view, as the prejudicial and erroneous attribution to mental illness as a causal factor in relation to violent behavior. This phenomenon has consequences in psychiatric clinical practice, but also at the level of social stigmatization, management of organizational and economic resources, and the judicial system. In this paper, clinical criticalities related to the psychiatrization of violent behavior will be analyzed, including the need to differentiate clinical etiology and legal causality, predictability and avoidability, protective clinical factors and clinical risk factors, the limits of categorical psychiatric diagnosis, the need for specific victimological information, the criticalities of pharmacotherapy. Some forensic criticalities will also be analyzed, including errors in clinical and forensic methodology (psychiatrization of the symptom, prejudicial contamination, diagnostic overshadowing, legal causalization of protective and risk factors, the use of categorical diagnosis in the forensic field, the psychiatrization of non-pathological human experiences, the criminalization of the subject with mental disorder). In conclusion, it is highlighted that an individual can have a psychic disorder, even severe, but this disorder is not necessarily in a causal relationship with violent behavior. The lack of a causal relationship makes predictability of violent behavior difficult, even impossible depending on the case, both in the general population and in individuals with psychiatric disorders.