Psychology and Crime News has this post on the Gudjonsson Suggestibility Scales. I had not previously heard of this instrument, but it may be coming soon to a courtroom near you.

People who are high in IS [interrogative suggestibility] are more susceptible to making false confessions under interrogative pressure, in a police or military interrogation scenario, for instance. However, as the authors point out, some offenders might be motivated to appear suggestible or vulnerable even if they are not. For instance, if an offender wanted to retract a statement or confession, or “in circumstances where the successful demonstration of vulnerability may lead to a reduction in a fine or sentence or even to escaping a custodial sentence”.

The problem is explored in a forthcoming article: Julian Boon, Lynsey Gozna and Stephen Hall (in press). Detecting ‘faking bad’ on the Gudjonsson Suggestibility Scales. Personality and Individual Differences