The rape trauma syndrome involves characteristic psychological effects derived from the trauma of the rape event. Although rape law has progressively attempted to shift the focus of rape trials from the victim's behavior to that of the defendant, evidence of the victim's lack of consent continues to be a critical factor in persuading a jury to convict. The use of expert testimony on rape trauma syndrome could help to establish the victim's lack of consent. In evaluating the admissibility of expert testimony, the majority of jurisdictions use the Frye test, which requires that the scientific evidence presented be generally accepted by the relevant scientific community. The Kansas, Minnesota, and Missouri Supreme Courts have accepted rape trauma evidence under the Frye test. Regarding the relevance of such evidence to the nonconsent element of rape, however, courts have reached opposite conclusions. They do not agree on whether or not rape-trauma evidence is helpful or prejudicial to juries. So long as the trial judge closely supervises the admission of rape-trauma-syndrome testimony, it should be admitted due to its being the best and often the only evidence relevant to the consent issue in rape cases. 194 footnotes.