Just Cognition: Scientific Research on Bias and Some Implications for Legal Procedure and Decision‐Making

Common law judges have traditionally been concerned about bias and the appearance of bias. Bias is believed to threaten the administration of justice and the legitimacy of legal decision‐making, particularly public confidence in the courts. This article contrasts legal approaches to bias with a range of biases, particularly cognitive biases, familiar to scientists who study human cognition and decision‐making. Research reveals that judges have narrowly conceived the biases that threaten legal decision‐making, insisting that some potential sources of bias are not open to review and that they are peculiarly resistant to bias through legal training and judicial experience. This article explains how, notwithstanding express concern with bias, there has been limited legal engagement with many risks known to actually bias decision‐making. Through examples, and drawing upon scientific research, it questions legal approaches and discusses the implications of more empirically‐based approaches to bias for decision making and institutional legitimacy.     

Deconstructing the Criminal Defence of Insanity

The significance of this article is in its deconstruction of the criminal insanity defence in a meta-legal critical context. The article’s objective is to critically review beliefs that the insanity defence was designed solely for public protection from insane violent people, or, for criminal deterrence. Arising from the long and continued use of the Roman Law concept of non compos mentis, the question arises as to what has become of the practical meaning of the term “insanity”, when used as a defence. The article tries to show that the defence of insanity is a public act of judicial denunciation against the accused, while the accused may have no effective responsibility for the crime. Argument begins with a critical discussion on the character of common-place denunciation as an appeal to public agreement. Then, it follows how the idea of “manifest criminality”, of the 1800s, might be cognate to modern ideas of “manifest madness”, linking into the origins of the English special verdict of insanity. This will allow a short critical analysis of the M’Naghten Case. Argument is completed with analysis of a psychologists’ expert construct of insanity and its relationship to jury perception. The article will suggest strongly that arguments based on the common law rules of insanity tend to expose juries more to denunciation of the accused, than to a reasoned account of the nature of his insanity and to the defects in his responsibility. Duly persuaded jurors would tend to acquiesce and participate in the denunciation of an accused person, whose unusual and unhealthy behaviours emanated from his sufferings by dint of his unbearable circumstances.     

The Impact of Police Strength and Arrest Productivity on Fear of Crime and Subjective Assessments of the Police

We explore the effect of police strength and arrest productivity on citizens’ fear of crime and perceived risk of victimization, as well as their subjective perceptions of the police including their confidence in the police and ratings of police response time. Police strength is measured as the rate of officers per 1,000 and productivity is calculated as the average number of arrests per officer; we also controlled for the crime rate using crimes reported to the police. We use nationally representative survey data (n?=?1,005) and conduct a supplemental analysis of data drawn from a representative sample of urban counties (n?=?1,500). Police force size and productivity have limited and inconsistent effects on fear of crime, perceived risk, and ratings of response time and no apparent effects on confidence in the police. We also find a modest yet statistically significant negative effect of police confidence on fear of crime. Our findings indicate that it is questionable whether adding more police will reduce fear or perceived risk of victimization to any measurable degree. Consequently, we suggest that rather than hiring binges and increased arrests, the focus should be instead on making positive contacts with citizens.     

Confidence interval of the likelihood ratio associated with mixed stain DNA evidence

Likelihood ratios are necessary to properly interpret mixed stain DNA evidence. They can flexibly consider alternate hypotheses and can account for population substructure. The likelihood ratio should be seen as an estimate and not a fixed value, because the calculations are functions of allelic frequency estimates that were estimated from a small portion of the population. Current methods do not account for uncertainty in the likelihood ratio estimates and are therefore an incomplete picture of the strength of the evidence. We propose the use of a confidence interval to report the consequent variation of likelihood ratios. The confidence interval is calculated using the standard forensic likelihood ratio formulae and a variance estimate derived using the Taylor expansion. The formula is explained, and a computer program has been made available. Numeric work shows that the evidential strength of DNA profiles decreases as the variation among populations increases.     

The effect of perceived risk and victimization on plans to purchase a gun for self-protection

Purposes

To determine if perceived risk of criminal victimization, and past criminal victimization experiences, increases the likelihood of a person owning a gun for self-protection, and to determine if defects in past research concerning the way gun ownership was measured had obscured such effects.

Methods

We analyzed data on over 2,500 U.S. adults, using different ways of measuring gun ownership, and also analyzed future plans (among persons who did not own a gun at the time of the survey) to acquire a gun for self-protection. The latter procedure avoids the causal order problem attributable to the possibility that acquiring a gun might affect victimization risks and perceived risks, as well as the reverse.

Results

The estimated effect of perceived risk and prior victimization changed from being nonsignificant when household gun ownership was the dependent variable (as in most prior research) to being increasingly strong, and statistically significant, when gun ownership of the individual respondent for defensive reasons was measured. Further, once the causal order issue was side-stepped, risk and victimization showed even stronger, significant positive effects on planning to get a gun.

Conclusions

Crime affects gun ownership, in addition to any effects that gun ownership may have on crime.     

Catching the Bad Guy: Morphing Composite Faces Helps

Composite faces built by eyewitnesses commonly are poor likenesses of the target face. When there are multiple witnesses, however, an opportunity exists to morph the composites. Morphs were rated as more similar to the target face than were the mean ratings of the individual composites. However, as hypothesized, the morph also came to resemble non-target faces more than the individual composites did (a prototype effect). This prototype effect was so strong that the morphs resembled non-targets more than the individual composites resembled the targets. In addition, morphing composites produced an attractiveness bias, which made the morphing of composites less effective for less attractive targets. Even when the prototype effect and the attractiveness bias were controlled for, however, a true morph-superiority effect continued to exist. The author won the Psi Chi/APS Albert Bandura Graduate Research Award in 2005--2006 for this study.     

Ventilatory and metabolic demands during aggressive physical restraint in healthy adults

We investigated ventilatory and metabolic demands in healthy adults when placed in the prone maximal restraint position (PMRP), i.e., hogtie restraint. Maximal voluntary ventilation (MVV) was measured in seated subjects (n=30), in the PMRP, and when prone with up to 90.1 or 102.3 kg of weight on the back. MVV with the heaviest weight was 70% of the seated MVV (122+/-28 and 156+/-38 L/min, respectively; p<0.001). Also, subjects (n=27) were placed in the PMRP and struggled vigorously for 60 sec. During the restrained struggle, ventilatory function (V(E)/ MVV) was 44% of MVV in the resting PMRP. While prone with up to 90.1 or 102.3 kg on the back, the decrease in MVV was of no clinical importance in these subjects. Also, while maximally struggling in the PMRP, V(E) was still adequate to supply the ventilatory needs.     

Using Gas Chromatography with Ion Mobility Spectrometry to Resolve Explosive Compounds in the Presence of Interferents*

Abstract: Ion mobility spectrometry (IMS) is a valued field detection technology because of its speed and high sensitivity, but IMS cannot easily resolve analytes of interest within mixtures. Coupling gas chromatography (GC) to IMS adds a separation capability to resolve complex matrices. A GC‐IONSCAN^® operated in IMS and GC/IMS modes was evaluated with combinations of five explosives and four interferents. In 100 explosive/interferent combinations, IMS yielded 21 false positives while GC/IMS substantially reduced the occurrence of false positives to one. In addition, the results indicate that through redesign or modification of the preconcentrator there would be significant advantages to using GC/IMS, such as enhancement of the linear dynamic range (LDR) in some situations. By balancing sensitivity with LDR, GC/IMS could prove to be a very advantageous tool when addressing real world complex mixture situations.