When Are Witnesses More Likely to Make Stuff Up?
September 28, 2012 1 Comment
Research on the “forced fabrication paradigm” demonstrates that when people generate fictitious information to explain unknown events, they will eventually come to believe the information is true. This has implications for how leading questions can affect the memories of witnesses, but little is known about the specific circumstances under which people are more or less likely to believe their own fabrications. A new study by Quin Chrobak and Maria Zaragoza provides one potential answer — that people are more likely to believe fabrications when the fabrications provide a causal explanation for why something has happened:
In the present study we provide the first evidence that the search for explanatory coherence also plays a role in the memory errors that result from suggestive forensic interviews. Using a forced fabrication paradigm (e.g., Chrobak & Zaragoza, 2008), we conducted 3 experiments to test the hypothesis that false memory development is a function of the explanatory role these forced fabrications served (the explanatory role hypothesis). In support of this hypothesis, participants were more likely to subsequently freely report (Experiment 1) and falsely assent to (Experiment 2) their forced fabrications when they helped to provide a causal explanation for a witnessed outcome than when they did not serve this explanatory role. Participants were also less likely to report their forced fabrications when their explanatory strength had been reduced by the presence of an alternative explanation that could explain the same outcome as their fabrication (Experiment 3).
It seems as though emphasizing a causal role would be useful in any situation in which you’re trying to convince somebody of a certain reality. For instance, if you want people at work to think you’re a great employee, try to arbitrarily attribute random things to the fact that you’re a great employee (e.g. “The reason Bob let me leave early on July 3rd because is that I’ve been working really hard.”)
When it comes to actual witness testimony, I’m torn about the validity of this kind of research. To me it’s questionable whether people who knew it was important that they remember something would fall victim to these fabrications. When you sees a random video clip in a lab, you don’t make it a cognitive priority to keep track of what happened. You use the simplest heuristic possible to judge events — if the thought was once in your head, it’s probably true. But if you’re a witness in a murder trial, you might dedicate extra cognitive resources to keeping track of what you actually saw. That’s not to say the pressures of the situation wouldn’t cause certain people to believe fabrications, but I wonder what would happen in an experiment containing a large ecologically valid sample — say, 60 real trial witnesses being observed during their initial interrogations. At the very least it would be interesting to see these experiments replicated but with “high value” and “low value” stories. That might reveal whether people are less likely to believe fabrications when they know a particular truth is more important.
Chrobak, Q.M., & Zaragoza, M.S. (2012). When Forced Fabrications Become Truth: Causal Explanations and False Memory Development Journal of Experimental Psychology: General DOI: 10.1037/a0030093