Twenty-four gender-balanced panels containing six mock jurors each viewed a videotaped simulation of a criminal court trial in which the age of the child victim/witness (6, 9, or 12 years), the child's gender, and the presence or absence of expert testimony were manipulated. Results revealed significant effects of exposure to expert testimony on jurors' ratings of the child on the factors addressed by the expert: expertise of memory, susceptibility to suggestion, and ability to monitor reality. The jurors rated the expert testimony highly in terms of its helpfulness and impartiality. No significant main effects were revealed for child credibility ratings according to the age or sex of the child victims. However, juror gender polarization effects were noted in that female jurors were significantly more likely than males to rate the child's credibility higher and to find the defendant guilty. Table and 53 references (Author abstract modified)