Andrew L. Urban
Tunnel vision compromised the police investigations into the deaths of Bob Chappell in Tasmania and five members of the Lin family in NSW (two of many examples), with Sue Neill-Fraser convicted of the former and Robert Xie convicted of the latter. Both wrongly, we firmly believe. It also happens in science, where it has another name: motivated reasoning.
Psychologist Brian Nosek of the University of Virginia claims that the most common and problematic bias in science is ‘motivated reasoning’. People that have a ‘dog in the fight’ (reputational, financial, ideological, political) interpret observations to fit a particular idea that supports their particular ‘dog.’
In law enforcement this is known as ‘tunnel vision’.
People’s beliefs become more extreme when they’re surrounded by like-minded colleagues. They come to assume that their opinions are not only the norm but also the truth – creating what social psychologist Jonathan Haidt calls a ‘tribal-moral community,’ as Judith Curry writes in Climate Etc. It’s not hard to imagine how that works within a group of detectives …
Psychologists Cusiman and Lombrozo found that people facing a dilemma between believing an impartial assessment of the evidence and believing what would better fulfil a moral obligation, people often believe in line with the latter. Cuisman and Lombrozo found that morally good beliefs demand less evidence than morally bad beliefs.
Motivated biases, they say, become particularly problematic once these biases are institutionalized, with advocacy statements made by professional societies, editorials written by journal editors, and public statements by the IPCC leadership. Likewise, the equivalent of such advocacy statements are those by prosecutors and journalists which also become ‘particularly problematic’ in the criminal justice system.
Arguably the most important of [such] conflicts between the responsible conduct of research (investigation) and larger ethical issues associated with the well-being of the public and the environment (justice). Fuller and Mosher’s book Climategate: The CruTape Letters argued that ‘noble cause corruption’ was a primary motivation behind the Climategate deceits. Noble cause corruption is when the ends of protecting the climate (noble) justify the means of sabotaging your scientific opponents (ignoble).
The parallel of noble cause corruption in law enforcement is the conviction of the suspect (noble) justifying the means of biased investigation (ignoble). Obviously, tunnel vision does not guarantee the conviction of the guilty. This is a serious problem for the criminal justice system and society as a whole.
Although a well known ailment in police circles, treatment for tunnel vision is virtually non-existent. It begins with culture reforms and special training that are uncomfortable for the participants, and reluctantly (if ever) imposed by the leadership.
NB: Lest this article be seen as a reflection of an anti-police bias, we should restate our support for the rule of law and the great majority of decent, honest and dedicated police officers.