Introduction: Expert testimony on violence victims also includes victims of sexual assault. The role of an expert is to classify the injuries by their severity, as defined in art. 157, 156 or 217 of the Criminal Code pertaining to crimes against health and life. Also, the role of an expert opinion is to determine whether the injuries identified during the exam occurred at the time and under the circumstances stated in medical history. The examination of sexual assault victims is conducted by two experts: a gynecologist and a forensic physician. Most examinations are performed at different times and various medical centers. The conclusions are presented in an official report. Regardless of victim age, all sexual crimes are investigated ex officio by the Police Department and the Prosecutor’s Office. Further legal classification of criminal offenses is the task of an appropriate legal body, and the offenses are codified in accordance with the provisions of chapter XXV of the Criminal Code, articles 197 - 205. In controversial cases, i.e. when two different expert opinions appear on the same case, or if, according to the law enforcement, a medical opinion is insufficient for some reason, an appropriate expert or team of experts is appointed to resolve the problem. Objectives: To present selected cases of sexual violence victims treated at the Department of Gynecology and assessed at the Department of Forensic Medicine with reference to the challenges regarding qualification of the sustained injuries and clinical diagnoses. Material and methods: Research material included selected forensic opinions developed for law enforcement offices that involved victims of sexual violence. The expert opinions were prepared either on the basis of submitted evidence, or both, submitted evidence and examination of the victim at the Department of Forensic Medicine. Moreover, the article presents a case of a patient examined and treated at the Department of Gynecology in Poznan. Conclusions: Based on the selected cases, the authors conclude that a medico-legal expert cannot uncritically accept previous diagnoses. Moreover, every expert is given the right and obligation to verify them. The need for complete, rapid and almost simultaneous colaboration between physicians in charge of the case, forensic doctors, police officers and prosecutors was demonstrated. Lack of cooperation may give rise to different opinions, leading to unnecessary elongation of the medico-legal procedures. It was observed that time plays a crucial role if qualification of an injury is required. The obligation of medical staff to inform the law enforcement about all cases of child abuse was also emphasized.