When an application is given a medical expert evidence of expertise includes points that attempt to measure the existence of a psychic damage on the victim as a result of the fact that has led to the trial, it should be noted that the appointed specialist will have to apply implementation of a Psycho as a complementary, then present your opinion in the case. This psycho-diagnostic, performed by a professional of psychology, must be administered and evaluated with the same technical precision and detail that a psychological expertise and the findings should be properly based on the partial results obtained during the process. The existence of a unique expertise in the case and the role of psychologists as a professional located outside of special care process determine the task, and you should never lose sight of the meaning and purpose of the examination is required. Often these studies are conducted in public hospitals, which are not normally experienced professionals the fields of forensic psychology and where, in addition, diagnostic tools and time on task are scarce. Often the report will be limited to a clinical evaluation by means of a short interview and there will be an assessment of disability. Mental Health Service and the Hospital will comply with the formality of the task entrusted to him, but the result is a weak point where you can probably attacked the opinion of an expert with the consequent risks. While “public perception” provided by the official stamps gives some consistency, a request for explanations formulated with professional advice can seriously compromise the value of the procedures and conclusions. On the other hand, the significant delay until the assessment is not only wasteful from the standpoint of judicial proceedings, but also the possible reduction in the severity of symptoms presented by the victim. Even in cases where the designation is sought a forensic medical expert, or requested a medical expert orthopedic surgeon and a psychiatrist, it is always advisable to offer psychological expert evidence. The characteristics of the process, the objectification of the findings by the administration and technical evaluation of psychometric and projective aspects, will allow diagnostic tools that may go unnoticed during the observation and clinical assessment of the medical examination own charge an importance value at the time of the clinical picture corresponds to the values of failure considered in the scales.