Memory researchers have speculated for a long time whether certain interventions can be used to get people to remember crimes that never started but still produce alleged confessions that lead to legal convictions.
Julia Shaws - University of Bedfordshire, Luton, England - and Stephen Porter - University of British Columbia, Vancouver, Canada - undertook a study on this topic, which for the first time provides evidence that memories can be created in a controlled experimental setting , which are characterized by completely presented action sequences. Using suggestive memory retrieval techniques, participants were reminded of criminal and non-criminal emotional episodes. The study compared these false memories with true memories of emotional events.
After three consecutive interviews, it was found that 70 percent of the selected participants had false memories of crimes (theft, robbery, or use of arms) that allegedly led to police investigations against them and an apparently wrong imagined confession. The false memories of criminal offenses described by those concerned were similar to the memories induced by test subjects of non-criminal imaginary events as well as of induced memories of real events. Reality and mere ideas could not be distinguished from one another because of the "authentic" descriptions and "remembered" multisensory impressions of those affected.
It therefore appears to be provable that in the context of a highly suggestive interview, people actually develop impressive false memories of crimes not committed.
From this it can be deduced that confessions are not reliable evidence under certain survey circumstances and that even lie detector tests by “perpetrators” can be manipulated. Evidently, more “objective” evidence is required to establish guilt and innocence beyond doubt.
Source: Shaw, Julia; Stephen Porter, “Constructing Rich False Memories of Committing Crime”; in: Psychologocal Science: January 14, 2015