Judges assume that gruesome evidence can influence juror verdicts, but little is known about the manner in which the influence is manifested. In a 2 x 3 study that varied the gruesome content of photographic and verbal evidence, gruesome verbal evidence did not influence mock juror emotional states, and had no impact on the conviction rate. Mock jurors who saw gruesome photographs, compared with those who saw no photographs, reported experiencing significantly more intense emotional responses, including greater anger at the defendant. The conviction rate when visual evidence in the form of gruesome or neutral photographs was included was significantly higher than the conviction rate without photographic evidence. Mean ratings of the inculpatory weight of prosecution evidence by mock jurors presented with gruesome photographs were significantly higher than those by mock jurors who did not view any photographs. Further analyses revealed that mock juror anger toward the defendant mediated the influence of the gruesome photographs in enhancing the weight of inculpatory evidence.