Archive for the ‘Forensic evidence’ Category
This is a fascinating study on how those that kill significant others or family members are different from those who kill strangers. The first author explains how these murderers are different, saying
“These murders are usually in the heat of passion and generally involve drugs or alcohol and often are driven by jealousy or revenge following a separation or a split. This is grabbing the kitchen knife out of the drawer in a fit of anger and stabbing her 42 times.”
The differences between those that kill family members and those that kill others are striking. The authors think the differences may mean we can discern a “criminological phenotype” and perhaps prevent family homicides. The researchers interviewed 153 men and women charged with and/or convicted of first degree murder in Illinois, Missouri, Indiana, Colorado and Arizona who were referred for neuropsychological evaluations to determine fitness to stand trial, criminal responsibility or to determine appropriate sentencing.
Each participant received a “detailed clinical interview, comprehensive neuropsychological assessment, review of pertinent records including police reports, crime scene photographs, autopsy reports, criminal history reports, correctional records, court documents, and interviews of collaterals and attorneys”. The participants were largely male (88.2%) and African-American (64.7%), ranged in age from 15 years of age to 67 years of age (with an average age of 33.1 years), and had a wide range of education—with an average education of 10.5 years and a range of 4 years education to 19 years.
Firearms were the most common weapon (40.5%), then knives (29.4%), and strangulation or suffocation (15.7%). Other weapons “included baseball bats, hammers, clubs, rocks and fists and other methods included drowning and fire (22.2%)”. The total number of victims for the 153 participants was 263 with the majority of murders (62.1%) involving one victim. For male perpetrators, almost half (48.4%) the victims were women. Female perpetrators killed nearly twice as many men (65%) as women.
As is often the case in research, there were no significant differences in the groups (those who killed family members and those who killed others) with regard to multiple demographic variables (e.g., age, education, ethnicity, employment). There were also no differences between the groups in terms of neurologic history, neurodevelopmental history, history of abuse (physical or sexual) or lifetime prevalence of drug use. Both groups had what the researchers call a “high incidence of illicit drug use and head trauma and a high prevalence of psychiatric disorders”.
Features common to both groups were a high prevalence of head trauma (80%), a history of special education (52.9% compared to a national average of 7.66%), psychotic disorders (45.1% in the spontaneous domestic homicide perpetrators and 19.4% in the non-domestic homicide perpetrators compared to about 3% average in the community), substance abuse histories consistent with prison inmates in general and incarcerated homicide offenders which the authors think may have further weakened already low inhibitions against homicide.
Here is a list of how those that murder family members (the authors refer to this as “spontaneous domestic homicide”) are different from those who kill others (non-domestic homicides).
They were twice as likely to carry a diagnosis of a psychotic disorder but less likely to have a diagnosis of antisocial personality disorder.
They were more likely to have been prescribed an antipsychotic or antidepressant and slightly less likely to have a prior history of felony convictions.
The average number of victims was lower for those that killed family members than those who killed non family members.
They were less likely (14%) to use a gun in their crimes compared to non-domestic homicide perpetrators (59%). They were more likely instead to use knives, baseball bats, clubs, or fists.
They had lower IQ scores and poor attention, executive function and memory but language skills were about the same.
The authors think these differences may be useful in discerning when concerned family members are at risk for harm and help them understand when it is time to remove themselves from the situation before it is too late. This article, while frightening to read, is a good step toward knowing when an impaired family member is dangerous and breaking through the denial that a family member would not hurt you. These are probably good things to know.
Hanlon, R., Brook, M., Demery, J., & Cunningham, M. (2015). Domestic Homicide: Neuropsychological Profiles of Murderers Who Kill Family Members and Intimate Partners Journal of Forensic Sciences DOI: 10.1111/1556-4029.12908
We’ve written about narcissists a fair amount here and today’s post shows us that the brains of narcissists are indeed very special—but not in a good way since they have “weakened frontostriatal connectivity”. But you probably knew that already. It’s a sort of neural disconnect, say the authors, between the self and reward. That disconnect may lead the narcissist to seek excessive reassurance from others.
Researchers from the University of Kentucky at Lexington recruited 50 undergraduate students and asked them to complete the Narcissistic Personality Index. Then they completed a specialized form of MRI with the participants: diffusion tensor imaging (a tool to measure the amount of connectivity between different brain areas). A very simplistic explanation of the technology is that it produces a spiderweb-like visualization of connections between different areas of the brain—you can literally see how much various parts of the brain are communicating.
The researchers were especially interested in an area known as the medial prefrontal cortex (MPFC) which is associated with thinking about ourselves, and a second and deeper region of the brain that is associated with reward and feeling good (the ventral striatum).
Even more specifically, they were interested in what they call “the density of the white matter tracts” between the two areas. The “white matter density” would highlight the level of connectivity between these areas of the brain—or, in other words, it would tell us how much these two areas of the brain are talking to each other. How often is the individual experiencing reward and feeling good about themselves?
So, the participants who have completed a measure of narcissism are lying in the MRI machine and having the number of connections between these two areas of the brain measured. Narcissists would say they have very high self-esteem and if that were true, they would have a high number of connections between these two parts of the brain since someone with high self-esteem would internally say nice things about themselves often.
Alas for the narcissists, the specialized brain scan did not show they had strong self-esteem. Instead, the higher the participants scored on the narcissism measure, the fewer connections they had between these two areas of the brain.
The researchers considered the finding and concluded that they see this as indicative of an “internal deficit in self-reward connectivity” in narcissists. In other words, if the narcissist is not having many rewarding thoughts or feelings about the self, they may seek out praise and admiration from others. Finally, the researchers suggest that the brain’s white matter can be modified: “clinical interventions can readily alter white matter integrity”. This fact, they say, suggests another way for narcissists to feel better on their own: repeated self-affirmations. This could help the narcissist refrain from what the researchers describe as characteristic “exhibitionism and immodesty”.
While intellectually interesting, from a litigation advocacy standpoint, we don’t think anyone will be putting neural evidence of neediness on the witness stand soon. But this study still points out an important reality: narcissism may indicate neediness.
Understand what to do when faced with a narcissist (in this case, the narcissistic witness).
Draw out the narcissist in cross-examination by asking for a sharing of expertise. Let jurors see how self-involved and arrogant the narcissist is when unscripted.
Use this understanding (of narcissistic neediness) to help you interact without rancor with a narcissistic colleague, client, or supervisor.
Chester, DS Lynam, DR Powell, DK DeWall, CN 2015 Narcissism is associated with weakened frontostriatal connectivity: a DTI study. Social Cognitive and Affective Neuroscience.
Criminal psychopaths are a common topic we write about here. They are notoriously difficult to treat, but are so disturbing they make for fascinating study (and hopefully reading). Some say they are not treatable. They are highly likely to reoffend after incarceration and prison is neither a deterrent nor a punishment for many of them. So to see a research article on an actual treatment for the adult psychopath is noteworthy.
These researchers recruited 14 criminal psychopaths with long and very violent histories who were serving long-term sentences in forensic psychiatric institutions with high security regulations in Germany to take part in a neurofeedback training program. Neurofeedback involves hooking a person up to an EEG machine to monitor brain activity. The brain activity is displayed on a computer screen as a graphical object and the person involved attempts to move the graphical display by controlling their brain activity—and they are rewarded for so doing, as in a video game.
So the psychopaths had 25 training sessions (each about an hour-long) in neurofeedback spread out over about 3 months and afterwards, they demonstrated “improved control” over their brain activity and reported (in questionnaire completion) having “reduced levels of impulsivity and aggression”. Those with the most “improved control” reported larger reductions in their aggression.
The researchers say that they will need to do more research but these criminal psychopaths were able to improve their brain activity control and reported a decrease in the impulsivity and aggression that varied depending on how much they improved in their ability to control brain activity. I guess it’s comforting that they report lower aggression, but I’m not sure I’d accept the word of a psychopath on that. The researchers think it would be good to have outcome measures that were not reliant on self-reports from severely violent psychopaths and we would agree. Very, very strongly…
Let’s consider the life of the severe criminal psychopath serving a “long term sentence in forensic psychiatric institutions with high security regulations”. They must get very bored and this research presents an opportunity to have 25 hours over the course of three months away from their highly restricted routine. The sample is very small (only 14) and while they did improve in their ability to control their brain activity on an EEG monitor, that makes them completely unremarkable. It isn’t a terribly hard thing to do, it simply requires an effort. And they really have little else to do.
It’s an interesting line of inquiry though and we’ll watch for more on this one. At this point though, it is likely interesting but meaningless in the overall question of what we do with the severely violent criminal psychopath.
Konicar L, Veit R, Eisenbarth H, Barth B, Tonin P, Strehl U, & Birbaumer N (2015). Brain self-regulation in criminal psychopaths. Scientific reports, 5 PMID: 25800672
Our posts on women stalkers are often listed in internet searches that bring people to our blog. Women stalk. Women also kill. In fact, it is believed that about 16% of serial killers (about 1 in 6) are female. Although it is hard for many to see women as capable of extreme crimes like murder, the researchers whose work we feature today have no such illusions. [If you can’t wrap your brain around that notion, we suggest you spend an evening alone in your house with all of the lights turned down, and watch the film Monster, an account of the convicted female serial killer Aileen Wuornos.]
“Contrary to preconceived notions about women being incapable of these extreme crimes, the women in our study poisoned, smothered, burned, choked, shot, bludgeoned, and shot newborns, children, elderly, and ill people as well as healthy adults; most often those who knew and likely trusted them.”
This is a chilling article to read (likely because of our stereotypes of women as nurturing caregivers). The researchers used murderpedia.org to identify female serial killers and then followed up with research in newspapers, police reports, et cetera. They were able to verify every female serial killer listed in murderpedia.org as having killed in the United States between 1821 and 2014.
They ended up with a sample of 64 female serial killers who killed in the United States and were almost entirely (98.4%) born in the US as well. Here’s what female serial killers (FSKs) look like in the United States:
Most were White (55, 88.7%) with six (9.7%) being Black and one (1.6%) Latina.
They were married (54.2%), divorced (15.3%), widowed (13.5%), in long-term committed relationships (8.5%) and single (8.5%).
Some were well-educated with a third (34.6%) having college degrees, 19.2% had some college or post-high-school professional training, 15.4% were high school graduates, and 30.8% dropped out of high school.
They held a wide variety of jobs including nursing, teaching, and prostitution. Many (39.2%) worked in health-related positions (such as nursing, nurse aides, or health administration). Others (21.6%) had other direct caregiving roles (babysitter, homemaker with children). The remainder (39.2%) were employed in a wide variety of jobs ranging from “farmer, gang leader, custodian, prostitute, psychic, drug dealer, and waitress”.
On average, they were about 32 years old when they first began to kill, but the age range was from 16 to age 65 so there is considerable variation. Similarly, they had an average “killing time span” of 7.25 years but the range was from all murders being committed in a single year to murders committed over a 31-year period. The 64 FSKs in this sample averaged 6.1 victims with a range of 3-31 victims.
Nearly 40% in the sample experienced some form of mental illness, while nearly one-third (31.5%) had been either physically or sexually abused (or both) by either parents or grandparents in childhood, and by husbands or long-term partners in adulthood. Even in the absence of diagnosed mental illness, the authors report “dysfunctional personality characteristics” such as lying, manipulation or insincerity in many FSKs. It’s hard to imagine being surprised that serial killers might be insincere.
Most commonly they killed for financial gain but they also killed for power, revenge, notoriety, and excitement. Women did not generally sexually assault their victims, nor did they tend to mutilate or torture like we see with male serial killers.
Their tendency was to kill both men and women (67.3%) with some killing male victims only (20%) and others killing female victims only (12.7%).They knew all or most of their victims and, in fact, were related to most of their victims (e.g., their children, their spouse, fiancé, boyfriends, mothers, mothers-in-law, fathers, aunts, cousins, and nephews). In every case, they targeted at least one victim who had little chance of fighting back (e.g., a child, the elderly, or the infirm).
The upper class (socioeconomically) was rarely represented (4.3%) with most FSKs being middle class (55.3%) and a few less being lower class (40.4%).
Their most common method of killing was poisoning (they are four times more likely than men to drug their victims).
A summary table from the article itself shows the range of killing methods used by FSKs.
In short, women (like men) kill. But, say these researchers, women tend to kill for resources (e.g., profit, comfort, control) while men kill for sex (e.g., rape, sexual torture, mutilation).
Harrison, M., Murphy, E., Ho, L., Bowers, T., & Flaherty, C. (2015). Female serial killers in the United States: means, motives, and makings The Journal of Forensic Psychiatry & Psychology, 1-24 DOI: 10.1080/14789949.2015.1007516