One eyewitness to a robbery reports that the culprit was a male in his 40s with brown hair, wearing a light-coloured T-shirt. Another describes a blond man in his early 30s wearing a denim shirt. If you’re a police officer investigating the crime, whose memory do you trust?
Identifying which of two apparently credible but conflicting eye-witness statements to trust is a big problem for law enforcement agencies (as is deciding, in the case of a witness who has no incentive to lie, which among their memories are accurate). Now a new paper, reported in the Journal of Experimental Psychology, provides initial evidence for a new, objectively verifiable method for doing this. This work has, as the researchers write, “potentially far-reaching significance, not the least in the legal context.”
The fallibility of eye-witness memory has been well-documented by psychologists, including how alcohol intoxication undermines witness accuracy still further. In fact, psychological research into the foibles of human memory and the implications this has for legal proceedings is arguably one of the best examples of the discipline making a practical contribution to everyday life.
And yet, as Annelies Vredeveldt at VU University Amsterdam and her team explain in their new paper in Applied Cognitive Psychology, there is a striking gap in the literature: “despite the frequency with which people use cannabis, there is almost no research examining its effects on eye-witness memory.”
Around the world, more people than ever are locked up in prisons – estimated to be in excess of 11 million people, up by almost 20 per cent since the turn of the millennium (pdf). According to a recent House of Commons Briefing Paper the rate of increase is even higher than this in the UK where prison populations are at a record high. Many of these incarcerated individuals have intensifying mental health needs – for instance, the same briefing paper reports that UK rates of self-harm in prisoners were 25 per cent higher in 2015 than in 2014. Ahead of this week’s meeting of the All Party Parliamentary Group for Psychology on the topic of Mental Health in the Criminal Justice System, here we provide a digest of research into the mental health of prisoners.
Psychology can help people one person at a time, but it also holds the promise of changing society at a mass scale, through campaigns to change attitudes and behaviour. One such endeavour is the development of programmes to reduce the rates of sexual assault of women on university campuses. But in a literature review in Aggression and Violent Behavior, researchers from the University of California make the case that such programmes may not just be ineffective, but counterproductive.
Although criminal investigation has been transformed through technological developments in DNA, phone tracking, and online data, the way a detective works through a crime has remained much the same. The first suspect is often the true perpetrator, but not always, and snowballing biases continue to lead to miscarriages of justice. Proficient detectives need the ability to generate and evaluate different explanations and keep an open mind. New research in the Journal of Police and Criminal Psychology investigates whether it’s possible to use established tests of reasoning ability to identify who has the skills necessary for thinking this way.
Historically, the kind of false memories induced in volunteers by psychologists have been relatively mundane. For example, a seminal study used leading questions and the encouragement to confabulate, to apparently implant in participants the memory of getting lost in a shopping mall as a child. This reliance on mundane false memories has been problematic for experts who believe that false memories have critical real world consequence, from criminal trials involving false murder confessions, to memories of child abuse “recovered” during therapy using controversial techniques.
The discrepancy between psychologists’ lab results and their real world claims vanished abruptly in 2015 when Julia Shaw (based then at the University of Bedfordshire) and Stephen Porter (University of British Columbia) shocked the memory research community with their staggering finding that, over several interview sessions, and by using false accounts purportedly from the participants’ own caregivers, they had successfully implanted false memories of having committed a crime as a teenager in 70 per cent of their participants, ranging from theft to assault with a weapon. But now other experts have raised doubts about these claims.
The desire to catch people in a lie has led to the development of techniques that are meant to detect the physical markers of dishonesty – from the polygraph to brain scans. However, these methods are often foundwanting. The insights of cognitive psychologists have arguably fared better, based on the idea that lying is more mentally demanding than telling the truth – real knowledge is automatically called to mind when we are questioned, and this needs to be inhibited before we answer, leading to slower responses. Unfortunately new research in the Journal of Experimental Psychology: Applied seems to pour cold water on the idea of using these subtle reaction-time differences to develop objective (and cheap) measures to get at the truth. The findings suggest that all it takes to render this cognitive approach ineffective is a prepared false alibi.
What lies at the dark heart of psychopathy? Is it a lack or emotion and empathy, a willingness to manipulate others – or, perhaps, a failure to take responsibility for misdeeds? All of these traits, and many more, are viewed as aspects of a psychopathic personality. But there’s still a debate among experts about which of these are core, and which less important.
Now a new study of 7,450 criminal offenders in the US and the Netherlands, published in the Journal of Abnormal Psychology, has identified what the researchers believe are the psychopath’s most “central” traits . But while there were striking similarities in the data from the two countries, there were also intriguing differences. This raises the question: does the meaning of the term “psychopath” vary between cultures?
Any context that encourages us to focus on a person’s body, more than their mind, is said to lead to objectification, such as when, in a previous era, a Formula One fan looked upon an attractive “grid girl” dressed in revealing clothes.
Perhaps the most serious concern about objectification is that it can lead us to disregard the rights and experiences of the objectified person. For instance, past research has shown that we’re more inclined to blame a rape victim depicted in a bikini, and more willing to (hypothetically) administer painful tablets to men and women shown wearing swim wear, rather than fully clothed.
Now a study in Cortex has taken things further by showing that volunteers’ empathy-related brain activity was diminished when they saw an objectified woman suffering social rejection, as compared with a woman who wasn’t objectified.
Around the world, neuroscience evidence is being introduced into courtrooms at an increasing rate, including findings from behavioural genetics. Specifically, some legal teams for the defence have been allowed to argue that the defendant has a low activity version of the MAOA gene, which codes for an enzyme that regulates the levels of several neurotransmitters. In combination with experiencing child abuse or maltreatment, having this low activity gene has been linked with increased impulsivity, including aggression. Defense lawyers presumably hope that jurors will interpret this as meaning the defendant was less culpable for their violent crime. However, before now, little research has examined how jurors will treat this evidence.
For a new study in Behavioral Sciences and the Law, Natalie Gordon and Edie Greene presented 600 mock jurors (half were students, half were from the wider community) with a detailed trial summary based on a real US murder trial in which the defendant, already in jail for an earlier crime, had murdered his cell-mate. The jurors’ task was to decide whether he should face the death penalty.