Testimony Validity as a Function of Question Form, Atmosphere, and Item Difficulty

The effects of five kinds of questioning, two interpersonal atmospheres of interviewing, and five levels of item difficulty on the accuracy and completeness of testimony about a short film were tested in a legal interrogation setting. Subjects enjoyed the supportive style of interviewing more than the challenging style, but atmosphere had no important effect on recall performance.
The type of questioning produced almost no differences in affective or cognitive reactions. However, as the specificity of questions increased, so did the completeness of testimony. Accuracy of testimony showed slight decreases for more specific questions. The trade-off between accuracy and completeness was mediated by item difficulty. It was very pronounced for items of high difficulty and not apparent for items of low difficulty.
Leading questions by themselves or in interaction with atmosphere did not produce special distortions in accuracy.