Expert testimony pertaining to battered woman syndrome: its impact on jurors' decisions

Participants (N = 200) were presented with a criminal homicide trial involving a battered woman who had killed her abuser. Within the trial, both the response history (passive, active) and presence of expert testimony pertaining to battered woman syndrome (present, absent) were systematically varied. As well, half of the participants in each of these conditions were provided with a nullification instruction informing them that they were free to disregard the law and acquit should a strict application of the law result in an unjust verdict. Results indicated that, compared to the passive response condition, the mock jurors were no less receptive to the expert testimony in the active response condition. The impact of the testimony on participants' verdicts, however, was moderated by the nullification instruction. That is, although the presence of the testimony did result in greater verdict leniency, this only occurred when the mock jurors had been released from a strict application of the law. The implications of these findings are discussed.