Minimizing responsibility increases commission errors in a mock crime paradigm

Purpose. Empirical studies have demonstrated that feigning amnesia undermines memory for a mock crime. Not much is known about the effects of other culpability-reducing strategies on memory. The present study investigated what strategies participants use when they are instructed to minimize culpability and if these strategies undermine memory to a similar extent as claiming amnesia. Methods. Participants performed a mock crime. Next, they were either instructed to minimize culpability for this mock crime in a simulated interrogation or asked to respond honestly. One week later, memory for the mock crime was tested. Results. None of the participants claimed amnesia when trying to minimize culpability. Conversely, all participants fabricated an alternative account of their role in the crime. Compared with responding honestly on both tests, fabricating an alternative story on the first test undermined memory for the mock crime in terms of commission errors. Correct recall was unaffected. It appeared that this effect was related to story length: the longer the fabricated story, the more the commission errors when telling the truth 1 week later. Conclusions. Fabricating an alternative story (i.e. lying) did not compromise correct recall, but induced more commission errors. The findings are discussed in terms of possible underlying mechanisms