Purpose. Interrogative suggestibility, as measured by the Gudjonsson Suggestibility Scales (GSS), is an independent form of suggestibility arising in the forensic/legal context. So far, an unresolved issue that may have different implications when measuring suggestibility is to what extent the scales measure internalization of suggested materials or just compliance with the interrogator.
Methods. Internalization of suggested materials and compliance were here measured using a source identification task. In Experiment 1, participants were administered the GSS2 and immediately afterwards asked to perform the source identification task on the items presented in the scale. In Experiment 2, half of the participants were administered the source identification task immediately and half after a 24-hr delay.
Results. In both experiments a higher proportion of compliant responses were found. Participants internalized more suggested information after questioning (Yield 1) and made more compliant responses after negative feedback (Shift). In Experiment 2, participants in the delayed condition internalized less material than those in the immediate condition.
Conclusions: Different processes appear to underlie Yield 1 and Shift scores in the GSS2. The former may include both internalization of suggested materials and compliance, while the second appears to be mostly due to compliance with the interrogator. When administering the GSS2 in a forensic/legal context as vulnerability predictor for making false confessions, or proneness to develop false memories through the internalization of suggested material, including a source identification task may provide additional information on the type of coping style and memory characteristics of the examinee.