Template:M intro crime tunnel vision

By tunnel vision, we mean that “compendium of common heuristics and logical fallacies,” to which we are all susceptible, that lead actors in the criminal justice system to “focus on a suspect, select and filter the evidence that will ‘build a case’ for conviction, while ignoring or suppressing evidence that points away from guilt.” This process leads investigators, prosecutors, judges, and defense lawyers alike to focus on a particular conclusion and then filter all evidence in a case through the lens provided by that conclusion.

— The Multiple Dimensions of Tunnel Vision in Criminal Cases by Keith Findley and Michael Scott (2006)

Prosecutor’s tunnel vision
/ˈprɒsɪkjuːtəz/ /ˈtʌnᵊl/ /ˈvɪʒᵊn/ (n.)
The collection of biases and misconceptions that can lead prosecutors (and juries) to convict innocent people of heinous crimes. In putting this together, JC draws on The Multiple Dimensions of Tunnel Vision in Criminal Cases by Keith Findley and Michael Scott in the Wisconsin Law Review (2006) and Robert Cialdini’s Persuasion. We think this can form a useful template for all kinds of bad decision-making environments.

It seems to us there are three stages of a tunnel vision scenario: the conditions that might put you at risk of heading down the road to an unjustified conclusion; the conditions that push you down that road, and the conditions that keep you there once you have arrived.Call these “setting out”, “getting there” and “staying there”.

In order of appearance:

Setting out

Overconfidence: An unjustified belief in one’s own abilities and judgments. Prosecutors may be overly confident in their case and less likely to consider alternative theories or evidence.

Anchoring effect: The tendency to rely too heavily on the first piece of information offered when making decisions. Initial impressions or pieces of evidence can disproportionately influence a prosecutor’s case strategy and assessment of guilt.

Role pressure: The pressure to fulfil the expectations and responsibilities of one’s role. Someone analogous to the “to a man with a hammer, everything looks like a nail” syndrome: prosecutors may feel intense pressure to secure convictions due to career advancement considerations, public expectations, or institutional culture. The literal meaning of “iatrogenic” — an illness produced by the treatment.

Getting there

Confirmation bias: The tendency to search for, interpret, and remember information that confirms pre-existing beliefs or hypotheses. Prosecutors may give undue weight to evidence that supports their case and disregard or minimize evidence that contradicts it.

Selective information processing: Focusing on certain pieces of evidence while ignoring others. Prosecutors might only present evidence that strengthens their case and neglect exculpatory evidence that could help the defense.

Groupthink: Thinking or making decisions as a group in a way that discourages creativity or individual responsibility: Prosecutors might conform to the prevailing opinion within their office, stifling dissenting views and critical analysis of the case.

Reductionism: Drilling deep into technical details that, by themselves, and shorn of all context, seem to lead to one conclusion — especially one you are already anchored to — notwithstanding the wider picture

Staying there

Hindsight bias: In hindsight, people tend to think an eventual outcome was inevitable, or more likely or predictable, than originally expected. “Hindsight bias” is a means through which people project new knowledge (of actual outcomes) onto knowledge of the past (observed behaviour), without realising that the perception of the past has been tainted by the subsequent information.

Once a person becomes a prime suspect and prosecutors arrive at an outcome in their own determination of who they believe is guilty — hindsight bias suggests that, upon reflection, the suspect was the inevitable and likely suspect from the beginning. Evidence is malleable in light of this “realisation”.

There is also a “reiteration effect”: A reiteration effect is also linked to hindsight bias. Confidence in an assertion increases the more it is repeated, independent of its truth or falsity. Accordingly, the longer that police, prosecutors and witnesses live with a conclusion of guilt, the more entrenched their conclusion becomes, and the more obvious it appears that all evidence pointed to that conclusion from the very beginning. This “reiteration effect” makes it increasingly difficult for police and prosecutors to consider alternative perpetrators or theories of a crime.

Outcome bias: Like hindsight bias, outcome bias involves a process in which people project outcomes onto the past without realising the outcome information has influenced their perception of the past, but it does not reflect judgments about the likelihood of an event, but about the quality of a suspect’s decision. Subjects are more likely to judge as bad a suspect’s decision to operate when they are told the patient died during surgery than when told the patient survived.

Sunk cost fallacy: The inclination to continue an endeavour once money, effort, time or credibility has been invested, even when new evidence suggests the defendant might be innocent. (see also commitment when talking about persuasion)

Cognitive dissonance: The discomfort experienced when holding two conflicting cognitions. To reduce discomfort, prosecutors may rationalize or dismiss information that challenges their belief in the defendant's guilt.

Belief perseverance: Maintaining a belief despite new information that firmly contradicts it. Even in the face of strong contrary evidence, prosecutors may cling to their original theory.

Ethical blindness: The inability to see the ethical dimensions of a situation due to focusing on other aspects. Prosecutors might neglect the ethical implications of their actions in the pursuit of winning a case.