Amanda Knox

The recent release of Amanda Knox, a young American exchange student convicted and imprisoned in Perugia, Italy, in connection with the murder of her flatmate Meredith Kercher in 2007, has been widely reported in newspapers all over the world.  We don’t know if she was guilty as the trial court determined in 2009 or innocent as the appeals court determined last week. You can read a detailed account of the murder and the trials here. But let us look at some angles of persuasion illustrated in this case. 

Amanda Knox

Photograph from inquisitr.com

There was never any clear forensic evidence that linked Amanda to the dead flatmate’s murder. The prosecution could not point to any convincing motive either.  But as Ian Leslie writes in The Guardian (Amanda Knox: What’s in a Face?), the Italian investigators had already concluded from her body language that she was guilty. Edgardo Giobbi, the chief investigator, had declared that his team could establish her guilt by closely observing her “psychological and behavioural reaction during the interrogation.”  The young woman’s behaviour was “too cool and calm;” she also appeared to be hyper-sexed. Giobbi was so sure of her guilt that he went to the extent of saying that there was no need for other kinds of investigation to establish it.

Of course the police did bring in a lot of ‘evidence,’ confessions, and theories that showed Amanda’s role in the murder convincingly enough for the court to give her a 25-year prison sentence. It appears now that what persuaded the investigators to conclude that Amanda was guilty of murder was essentially her body language. Their instincts told them that she was guilty. Once they arrived at that conclusion, they were looking for evidence to justify it. 

Ian Leslie cites the results of experimental research conducted in 2008 by a group of Norwegian scientists to understand how police investigators judged the credibility of rape claims. The researchers found that the investigators, who were proud of their objectivity and ability to see through false claims, were heavily influenced by the demeanor of the victim. In their experiment, an actress played the role of a rape victim and used the same statement, but varied her emotions. She was perceived as telling the truth when her statement was accompanied by tears or a show of despair.  

Underlying such perception or judgement is a vague and unsubstantiated model we have in our mind about how others should behave in a given context. 

If seasoned police investigators who want to be objective can be influenced by people’s looks and behavior, can we be free from them? Can we be sure that when we are persuaded to buy a product, service, or idea in the world of business, our decision is driven primarily by evidence and rationality? When we reject others' proposals, can we be sure that we are driven by evidence and rationality? Could it be that something about the persuader triggers our instincts one way or the other and once we are persuaded, we look for evidence to justify the decision to ourselves and to others?