Many young children who understand the difference between truth and lies are nonetheless deemed incompetent to testify in court, according to developmental psychologist Tom Lyon ’87, “because lawyers ask them questions that are too abstract for their stage of development.” Lyon, an associate professor at the University of Southern California Law School, and psychology professor Karen Saywitz of Harbor-UCLA Medical Center have developed “a more reliable and cognitively appropriate alternative,” the Lyon-Saywitz Oath-Taking Competency Picture Task.

In part one, the questioner shows a child a series of six pictures: for example, in one picture, two boys are standing between an image of a familiar object such as a teddy bear. Each boy has a “talk-bubble” above his head; one boy’s talk-bubble contains a matching teddy bear, the other’s, a book. The questioner asks the child to identify which boy is telling the truth and which is lying—the boy who says that the dominant object is a bear or the one who says it’s a book.

Part two addresses the second competence children must demonstrate to testify — an understanding of the importance of telling the truth. In the “morality task,” the questioner shows the child a picture of two boys in front of a judge and identifies one of the boys as lying to the judge, the other as telling the truth. The questioner then asks the child to point to the boy who will get in trouble. This approach sidesteps another frequent prosecutor error—asking children what will happen to them if they lie, which may frighten them into silence.

Lyon, who hopes the test will be widely used, has distributed it, along with research supporting its effectiveness, to over 100 lawyers and will soon post it on a Web site.