A study of British twins appearing this week in the Proceedings of the National Academy of Sciences shows that an adolescent’s sense of their own family’s social and economic standing is closely linked to that child’s physical and cognitive health.
fact, the adolescent’s perception of status was a more powerful predictor of their
well-being and readiness for further education than their family’s actual
status. The study sample represented the full range of
socioeconomic conditions in the U.K.
“Testing how young people’s perceptions related to well-being among twins provided a rare opportunity to control for poverty status as well as environmental and genetic factors shared by children within the same family,” said lead author Joshua Rivenbark, an MD/PhD student in Duke’s Medical School and Sanford School of Public Policy.
“Siblings grew up with equal access to objective resources, but many differed in where they placed their family on the social ladder – which then signaled how well each twin was doing,” Rivenbark said.
Researchers followed 2,232 same-sex twins born in England and Wales in 1994-95 who were part of the Environmental Risk (E-Risk) Longitudinal Twin Study based at King’s College London. Adolescents assessed their family’s social ranking at ages 12 and 18. By late adolescence, these beliefs signaled how well the teen was doing, independent of the family’s access to financial resources, healthcare, adequate nutrition and educational opportunities. This pattern was not seen at age 12.
amount of financial resources children have access to is one of the most
reliable predictors of their health and life chances,” said Candice Odgers, a professor
of psychological science at the University of California, Irvine, who is the senior
author of the report. “But these findings show that how young people see their
family’s place in a hierarchical system also matters. Their perceptions of
social status were an equally good, and often stronger, indicator of how well
they were going to do with respect to mental health and social outcomes.”
findings also showed that despite growing up in the same family, the twins’
views were not always identical. By age 18, the twin who rated the family’s
standing as higher was less likely to be convicted of a crime; was more often
educated, employed or in training; and had fewer mental health problems than his
or her sibling.
that experimentally manipulate how young people see their social position would
be needed to sort out cause from effect,” Rivenbark said.
The E-Risk study was founded and is co-directed by Duke professors Avshalom Caspi and Terrie Moffitt at King’s College London.
Guest Post by Pat Harriman, UC-Irvine News @UCIPat
This is the sixth and final 2019 post written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.
Dr. Patrick Codd is the Director of the Duke Brain Tool Laboratory and an Assistant Professor of Neurosurgery at Duke. Working as a neurosurgeon and helping with the research and development of various neurosurgical devices is “a delicate balance,” he said.
Codd currently runs a
minimally invasive neurosurgery group. However, at Massachusetts General
Hospital, he used to run the trauma section. When asked about which role was
more stressful, he stated “they were both pretty stressful” but for different
reasons. At Mass General, he was on call for most hours of the day and had to
pull long shifts in the operating room. At Duke, he has to juggle surgery,
teaching, and research and the development of new technology.
“I didn’t know I was
going to be a neurosurgeon until I was in college,” Codd said. Despite all of
the interesting specialties he learned about in medical school, he said “it was
always neurosurgery that brought me back.”
Currently, he is
exclusively conducting cranial surgery.
Though Dr. Codd has earned
many leadership positions in his career, he said he was never focused on advancement.
He simply enjoys working on topics which he loves, such as improving minimally
invasive surgical techniques. But being in leadership lets him unite other
people who are interested in working towards a common goal in research and
development. He has been able to skillfully bring people together from various
specialties and help guide them. However, it is difficult to meet everyone’s
needs all of the time. What is important for him is to be a leader when he
needs to be.
Dr. Codd said there are typically five to eight research papers necessary in to lay the groundwork for every device that is developed. However, some technologies are based on the development of a single paper. He has worked on devices that make surgery more efficient and less minimally invasive and those that help the surgical team work together better. When developing technologies, he tries to keep the original purpose of the devices the same. However, many revisions are made to the initial design plans as requirements from the FDA and other institutions must be met. Ironically, Dr. Codd can’t use the devices he develops in his own operating room because it would be a conflict of interest. Typically other neurosurgeons from across the country will use them instead.
This is the fifth of six posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.
Research is a journey full of uncertainty in which scientists have to construct their own path, even if they’re unsure of what the end of the journey actually is. Despite this unpredictability, researchers continue their journey because they believe their work will one day drive their fields forward. At least, that’s why Kate Meyer Ph.D. says she has investigated something called m6A for several years.
“Virtually every study that I have ever been part of had
some frustrations involved because everything can fall apart in just one
night,” Meyer said. “Despite all the frustrations you might have, you are still
in the research because you know that at the end of the day, you will get new
knowledge that is worthy to your field, or perhaps to the world.”
N6-methyladenosine (or m6A) is a modification to one of the four main bases of RNA – adenosine. Because RNA plays a significant role as a bridge between genetic information and functional gene products, modifications in RNA can alter how much of a certain product will be produced, which then controls how our cells and eventually our whole body functions.
The idea of this tiny but powerful modification was first proposed in the 1970s. But scientists struggled to find where m6A was located in the cell before research Meyer made a major contribution to as a trainee was published in 2012. Combining a newly developed antibody that could recognize m6A and gene sequencing techniques that became more accessible to the researchers, Meyer’s work led to the first method that can detect and sequence all of the m6A regions in a cell.
Meyer’s work was transformative research. Her method allowed
laboratories around the world to investigate what regulates m6A and what its
consequences are. Meyer said this first study which ignited m6A field is one of
her most prideful moments as a researcher.
Significant progress has been made since 2012, but there are still lots of questions that need to be answered. Currently, Meyer’s research team is investigating the relationships between m6A and various neurological issues. She believes that regulation of m6A controls the expression, or activity level, of various genes in the brain. As such, m6A may play an important role in neurodegenerative diseases and memory.
As an assistant professor of both biochemistry and neurobiology at Duke, Meyer is definitely one of the most important figures in the m6A field. Despite her many accomplishments, she said she had experienced and overcome many frustrations and failures on her way to the results.
This is the fourth of several posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.
Dr. Giny Fouda’s research focuses on
infant immune responses to infection and vaccination.
Her curiosity about immunology arose during her fourth year of medical school in Cameroon, when she randomly picked up a book on cancer immunotherapy and was captivated. Until then, she conducted research on malaria and connected it to her interest in pediatrics by studying the effects of the parasitic disease on the placentas of mothers.
As a postdoctoral fellow at Duke, she
then linked pediatrics and immunology to begin examining mother to child
transmission of disease and immunity.
Today she is an M.D. and a Ph.D. and a
member of the Duke Human Vaccine Institute. She’s an assistant professor in
pediatrics and an assistant research professor in the Department of Molecular Genetics
and Microbiology at Duke University School of Medicine.
Based on the recent finding that children of HIV-positive mothers are more susceptible to inheriting the disease, Fouda believes that it is important to understand how to intervene in passive immunity transmissions in order to limit them. Children and adults recover from diseases differently and uncovering these differences is important for vaccine development.
This area of research is personally important to her, because she learned from her service in health campaigns in Central Africa that it is much easier to prevent disease than to treat.
However, she believes that it is important to recognize that research is a collaborative experience with a team of scientists. Each discovery is not that of an individual, but can be accredited to everyone’s contribution, especially those whose roles may seem small but are vital to the everyday operations of the lab.
At the Duke Human Vaccine Institute, Fouda enjoys collaborating as a team and contributing her time as a mentor and trainer of young scientists in the next generation.
Outside of the lab, Fouda likes to spend time reading books with her daughter, traveling, decorating and gardening. If there was one factor that improve how science in immunology is conducted, she would stress that preventing disease is significantly cheaper than treating those that become infected by it.
Dr. Fouda has made some remarkable progress in the field of disease treatment with her hard working and optimistic personality, and I know that she will continue to excel in her objectives for years to come.
This is the third of several posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.
Beneath Duke University’s Perkins library,
an unassuming, yet fiercely original approach to video games research is
underway. Tied less to computer science and engineering than you might expect,
the students and faculty are studying games for their effects on players.
I was introduced to a graduate researcher who
has turned a game into an experiment. His work exists between the humanities,
psychology, and computer science. Some games, particularly modern ones, feature
complex economies that require players to collaborate as often as they compete.
These researchers have adapted that property to create an economics game in
which participants anonymously affect the opportunities – and setbacks – of
other players. Wealth inequality is built in. The players’ behavior, they hope,
will inform them about ‘real-world’ economic decisions.
At the intersection of this
interdisciplinary effort with games, I met Shai Ginsburg, an associate professor in the
department of Asian and Middle Eastern studies who studies video games and
board games the way other humanities professors might study Beowulf.
For example, he is able to divide human history
into eras of games rather than of geopolitics.
“Until recently, games were not all that
interactive,” he says. “Video games are, obviously, interactive, but board
games have evolved, too, over the same period of time.” This shift is
compelling because it offers us new freedoms in the way we express human
“The fusion of storytelling and
interactivity in games is very compelling,” Ginsburg says. “We haven’t seen
that many games that handle issues like mental illness,” until more recently,
he points out. The degree of interactivity in a video game grants a player a
closeness to the narrative in the areas where writing, music, and visual art
alone would be restricted. This closeness gives game designers – as artists –
the freedom to explore themes where those artistic restrictions also hinder
However, Dr. Ginsburg is not a game
historian; the time that a game feature evolved is far less relevant to him than
how its parent game affects players. “We tend to focus on the texts that
interest us in a literature class,” he says, by way of example. He studies the
games that interest him for the play opportunities they provide.
One advantage of using games as a medium
to study their effects on people is that, “the distinction between highbrow and
lowbrow is not yet there,” Ginsburg says. In painting, writing, and plenty of
other mediums, a clear distinction between “good” and “bad” is decided
simultaneously by communities of critics and consumers. Not so, in the case of
This is the second of several posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.
As an occasional volunteer at a local children’s museum, I
can tell you that children take many different approaches to sharing. Some will
happily lend others their favorite toys, while others will burst into tears at
the suggestion of giving others a turn in an exhibit.
For Rita Svetlova Ph.D. at the Duke Empathy Development Lab, these behaviors aren’t just passing observations, they are her primary scientific focus. In November, I sat down with Dr. Svetlova to discuss her current research, past investigations, and future plans.
Originally from Russia, Svetlova obtained an M.A. from
Lomonosov Moscow State University in Moscow before earning her Ph.D in
developmental psychology from the University of Pittsburgh. She later worked as
a post-doctoral researcher at the Max Planck Institute for Evolutionary
Anthropology in Leipzig, Germany.
Now at Duke University as an assistant research professor of psychology and neuroscience and the principal investigator in the Empathy Development Lab, Svetlova looks at the development of ‘prosocial’ behavior in children — behaviors such as sharing, empathy, and teamwork.
Svetlova credits her mentor at the University of Pittsburgh,
Dr. Celia Brownell, for inspiring her to pursue child psychology and
development. “I’ve always been interested in prosociality, but when I was in
Russia I actually studied linguistics,” she says. “When I moved to the U.S., I
changed paths partly because I’ve always wanted to know more about human
psychology. The reason I started studying children is partly because I was
interested in it and partly because I met Dr. Brownell. I branched out a little
bit, but I generally found it interesting.”
Although her passion for childhood development research
began in Pittsburgh, Svetlova has
embraced her role as a Duke researcher, most recently tackling a scenario that
most academically-inclined readers are familiar with — a partner’s failure to
perform in a joint-commitment — in a co-authored May 2017 paper titled
“Three-Year-Olds’ Reactions to a Partner’s Failure to Perform Her Role in a
the study, 144 three-year-olds were presented with a common joint commitment
scenario: playing a game. For one third of the children, the game ended when
their partner defected, while another third of the test group had a partner who
didn’t know how to play. The final third
of the group saw the game apparatus break. Svetlova looked at how the
children’s reactions varied by scenario: protesting defectors, teaching the
ignorant partner, and blaming the broken apparatus. The results seem to suggest
that three-year-olds have the ability to evaluate intentions in a joint
paper Svetlova co-authored, titled “Three- and 5-Year-Old Childrens’ Understanding
of How to Dissolve a Joint Commitment,” compared the reactions of three- and
five-year-olds when a puppet left a collaborative game with either permission,
prior notification, or suddenly without prior notification. If the puppet left
without warning, three-year-old subjects protested more and waited longer for
the puppet’s return, but both age groups seemed to understand the agreement implicit
in a joint commitment.
joint commitments are only a small fraction of the questions that Svetlova
hopes to address.
longitudinal study of prosociality would be amazing,” she says. “What I’m
interested in now is the intersection of fairness understanding and
in-group/out-group bias. What I am trying to look into is how children
understand their in-group members vs. out-group members and whether there’s
something we can do to make them more accepting of their out-group members.”
one I am interested in is the neural basis of empathy and prosocial behavior. I
haven’t started yet, but I’m planning a couple of studies on looking into the
brain mechanisms of empathy in particular,” Svetolova says. “We plan to scan
children and adults while experiencing an emotion themselves and compare that
brain activation to the brain activation while witnessing someone experiencing
an emotion, the question being ‘do we really feel others’ emotions as our
also expressed her interest in the roles that gender, culture, and upbringing
play in a child’s development of prosociality.
had to ask her why teenagers seemed to “regress” in prosociality, seemingly
becoming more selfish when compared to their childhood selves.
“I would distinguish between self-centered and selfish,” she assured me. “You are not necessarily selfish, it’s just that during teenagehood you are looking for your place in the world, in the ‘pack.’ That’s why these things become very important, other’s opinions about you and your reputation in this little group, people become very anxious about it, it doesn’t mean that they become selfish all of a sudden or stop being prosocial.” She added, “I believe in the good in people, including teenagers.”
This is the first of several posts written by students at the North Carolina School of Science and Math as part of an elective about science communication with Dean Amy Sheck.
Claudia Gunsch, the Theodore Kennedy distinguished associate professor in the department of civil and environmental engineering, wants to know how to engineer a microbial community. An environmental engineer with a fascination for the world at the micro level, Gunsch takes a unique approach to solving the problem of environmental pollution: She looks to what’s already been done by nature.
Gunsch and her team seek to harness the power of microbes to create living communities capable of degrading contamination in the environment.
“How can you engineer that microbial community so the
organisms that degrade the pollutant become enriched?” she asks. “Or — if
you’re thinking about dangerous pathogenic organisms — how do you engineer the
microbial community so that those organisms become depressed in that particular
The first step, Gunsch says, is to figure out who’s there.
What microbes make up a community? How do these organisms function? Who is
doing what? Which organisms are interchangeable? Which prefer to live with one
another, and which prefer not living with one another?
“Once we can really start building that kind of framework,”
she says, “we can start engineering it for our particular purposes.”
Yet identifying the members of a microbial community is far
more difficult than it may seem. Shallow databases coupled with vast variations
in microbial communities leave Gunsch and her team with quite a challenge.
Gunsch, however, remains optimistic.
“The exciting part is that we have all these technologies
where we can sequence all these samples,” she says. “As we become more
sophisticated and more people do this type of research, we keep feeding all of
this data into these databases. Then we will have more information and one day,
we’ll be able to go out and take that sample and know exactly who’s there.”
“Right now, it’s in its infancy,” she says with a smile.
“But in the long-term, I have no doubt we will get there.”
Gunsch is currently working on Duke’s Superfund Research
Center designing bioremediation technologies for the degradation of polycyclic
aromatic hydrocarbon (PAH) contamination. These pollutants are extremely
difficult to break down due to their tendency to stick strongly onto soil and
sediments. Gunsch and her team are searching for the right microbial community
to break these compounds down — all by taking advantage of the innate
capabilities of these microorganisms.
Step one, Gunsch says, has already been completed. She and
her team have identified several different organisms capable of degrading PAHs.
The next step, she explains, is assembling the microbial communities — taking
these organisms and getting them to work together, sometimes even across
kingdoms of life. Teamwork at the micro level.
The subsequent challenge, then, is figuring out how these
organisms will survive and thrive in the environment they’re placed in, and
which microbial seeds will best degrade the contamination when placed in the
environment. This technique is known as “precision bioremediation” — similar to
precision medicine, it involves finding the right solution in the right amounts
to be the most effective in a certain scenario.
“In this particular case, we’re trying to figure out what
the right cocktail of microbes we can add to an environment that will lead to
the end result that is desired — in this case, PAH degradation,” Gunsch says.
Ultimately, the aim is to reduce pollution and restore
ecological health to contaminated environments. A lofty goal, but one within
sight. Yet Gunsch sees applications beyond work in the environment — all work dealing
with microbes, she says, has the potential to be impacted by this research.
“If we understand how these organisms work together,” she says, “then we can advance our understanding of human health microbiomes as well.”
In Queensland, Australia, early March can
be 96 degrees Fahrenheit. It’s summer in the Southern Hemisphere, but that’s
still pretty hot.
Although hot, dry Australia probably isn’t the first place you’d think to look for ferns, that’s precisely why I’m here and the sole reason we’ve hit the road at 6 a.m. Our schedule for the day: to drive as far south as we can while still letting us come home at the end of the day.
My local colleague, Ashley Field, grew up just the next town over. A skinny, speedy man, he works at James Cook University in Cairns and knows most of northern Queensland like the back of his hand.
The ferns I’m looking for today are
interesting because some species can move from their original home in Australia
to the tiny islands in the Pacific. But some cannot. Why? Understanding what
makes them different could prove useful in making our crops more resilient to
harsh weather, or preventing weeds from spreading.
We’ve been driving for four hours before we
turn off onto a dirt road. If you haven’t been to Australia, it’s worth noting
that four hours here is unlike any four hours I’ve experienced before. The
roads are fairly empty, flat, and straight, meaning you can cover a lot of terrain. Australia is also
incredibly big and most of the time you’re travelling through unpopulated
landscapes. While it may be only four hours, your mind feels the weight of the
The dirt road begins to climb into the
mountains. We are leaving behind low scrub and big granite rocks that sit on
the flat terrain. Ashley knows where we can find the ferns I’m looking for, but
he’s never driven this road before. Instead, we’re trusting researchers who
came before us. When they explored this area, they took samples of plants that were
preserved and stored in museums and universities. By reviewing the carefully
labelled collections at these institutions, we can know which places to revisit
in hopes of finding the ferns.
Often, however, having been collected
before there was GPS, the location information on these samples is not very
precise, or the plants may no longer live there, or maybe that area got turned
into a parking lot, as happened to me in New Zealand. So, despite careful
planning, you may drive five hours one way to come up empty handed.
As we move higher up the mountain, the soil
turns redder and sparse eucalyptus forests begin to enclose us. We locate the
previous collections coordinates, an area that seems suitable for ferns to
grow. We park the truck on the side of the road and get out to look.
We comb 300 feet along the side of the road because these ferns like the edges of forest, and we find nothing. But as we trudge back to the truck, I spot one meager fern hiding behind a creeping vine! It’s high up off the road-cut and I try to scramble up but only manage to pull a muscle in my arm. Ashley is taller, so he climbs partway up a tree and manages to fetch the fern. It’s not the healthiest, only 6 inches tall for a plant that usually grows at least 12 to 14 inches. It’s also not fertile, making it less useful for research, and in pulling it out of the ground, Ashley broke one of its three leaves off. But it’s better than nothing!
Ashley excels at being a field botanist
because he is not one to give up. “We should keep looking,” he says despite the
sweat dripping down our faces.
We pile back in and continue up the road.
And who could have predicted that just around the bend we would find dozens of tall,
healthy looking ferns! There are easily fifty or so plants, each a deep green,
the tallest around 12 inches. Many others are at earlier stages of growth,
which can be very helpful for scientists in understanding how plants develop.
We take four or five plants, enough to leave a sample at the university in
Cairns and for the rest to be shipped back to the US. One sample will be kept
at Duke, and the others will be distributed amongst other museums and
universities as a type of insurance.
The long hours, the uncertainty, and the
harsh conditions become small things when you hit a jackpot like this. Plus,
being out in remote wilderness has its own soothing charm, and chance also
often allows us to spot cool animals, like the frilled lizard and wallaby we
saw on this trip.
Funding for this type of fieldwork is becoming increasingly rare, so I am grateful to the National Geographic Society for seeing the value in this work and funding my three-week expedition. I was able to cover about 400 miles of Australia from north to south, visiting twenty-four different sites, including eight parks, and ranging from lush rainforest to dry, rocky scrub. We collected fifty-five samples, including some that may be new species, and took careful notes and photographs of how these plants grow in the wild, something you can’t tell from dried-up specimens.
Knowing what species are out there and how they exist within the environment is important not only because it may provide solutions to human problems, but also because understanding what biodiversity we have can help us take better care of it in the future.
Earlier this year, the online DNA testing company Ancestry.com faced a media firestorm and social media backlash after posting a controversial ad on its YouTube page.
Titled “Inseparable,” the 30-second ad depicted a white man in the antebellum South asking an
African-American woman to flee to the North with him. Before the woman can answer,
the piece cuts to a tagline: “Only you can keep the story going. Uncover the
lost chapters of your family history with Ancestry.” Many
criticized the ad’s historical inaccuracy, showcasing a rosier portrayal of a
complicated past. To extinguish flames, Ancestry completely pulled the ad from
A recent Duke study of dozens of other ads across multiple DNA testing companies shows that this isn’t the only example of mixed messaging about race and identity from the world of genetic ancestry tests.
The tests are quite simple: order a kit, send off a
saliva sample and receive an ethnicity estimate within weeks. A test taker’s
ethnicity is broken down into percentages based off their DNA matches compared
to a globally referenced DNA database. Kits can range in price from $79 to$400.
Sales of DNA testing kits had reached 12 million people by 2017, as reported by
As part of the six-week summer research program Story+, Duke students Dakota Douglas, Mona Tong and Madelyn Winchester analyzed the messaging in 90 video ads from the companies 23andMe, AncestryDNA and MyHeritageDNA to see what they promise consumers.
Many of the ads lured customers with promises of a newfound identity and possible family members, the team found. One Ancestry.com ad, entitled “Kyle,” depicts a customer whose childhood was steeped in German culture, but discovers as an adult that he is also part Scottish and Irish. He happily “traded in his lederhosen for a kilt,” completely forgoing his previous heritage and reducing a newly discovered culture to stereotypes.
“There were a lot of advertisements
similar to that one,” said team member Mona Tong. “Many found a new identity
embracing it fully despite a lack of any cultural connections.”
“Kyle” illustrates a
phenomenon described in a 2018 study from the
University of British Columbia, which found that people
tended to “cherry-pick” the results, identifying more with certain ethnicities
and cultures to appear different. Whites were more likely to see their results
as “transformational” than their nonwhite counterparts.
“It’s not a bad idea to test your genes
for medical reasons,” said Patricia Bass, the team’s project mentor. “However,
these ads can be misleading by assuming that someone’s cultural and racial
heritage are determined by genes.”
While the majority of subjects featured within the ads were white, the few ads that featured people of color often glossed over the complicated history of someone’s lineage or conveniently left out difficult topics. Ancestry’s “Anthem” ad detailed historical reenactments of an African tribal women, prohibition gangsters, a man fleeing England for America and Native Americans somberly heading to a new land. A voiceover speaks with inspiration ending with a shot of a biracial woman.
In marketing the idea that we
are all one, the ads fetishized
mixed-race subjects, while ignoring the genocide and displacement of people,
the team found.
The team hopes future
research will further examine the impact of these ads on people’s view of
identity. Importantly, one could note if there were any focus groups to test
these ads before release.
“It furthers the idea of colorblindness,”
Tong said. “It assumes that relationships are contingent upon common ancestry
“In a way, companies are trying to help
by focusing on the interconnectivity and commonalities between people,” Tong
said. “But it hurts more than it helps.”
Story+ is a six-week undergraduate research program offered through the John Hope Franklin Humanities Institute and Bass Connections, with support from the Duke University Libraries and Versatile Humanists at Duke.
This is the last of eight blog posts written by undergraduates in PSY102: Introduction to Cognitive Psychology, Summer Term I 2019.
In the criminal justice system, one might imagine that the
more serious a crime is, the more extensive the evidence should be to support
the verdict. However, a recent study conducted
at Duke University finds that jurors assessment of guilt is less reliant on
the type of evidence and more on the severity of the crime.
Mock jurors in the study were more likely to find someone
charged with murder guilty than someone charged with robbery.
Numerous scholars have looked at how flawed forensic
evidence, mistaken eyewitness identifications and defendants’ prior criminal convictions
can introduce errors in criminal prosecutions.
Pearson, an assistant professor in four Duke departments including
neurobiology, and his colleagues in law wanted to know whether the type of
crime can also lead to a greater chance of wrongful conviction. It may be that jurors
use moral and emotional responses to various crimes as reasoning for the
decisions they make regarding the defendant’s guilt.
The researchers aimed to understand the relationship between
crime severity and confidence in guilt by seeing how mock jurors, practicing
prosecutors, and other practicing lawyers weigh various types of evidence in
order to make a decision on guilt.
Participants in the study were subjected to about 30 crime
scenarios, each one paired with a random variety of types of evidence. After
participants read through each respective scenario, they rated the strength of
the case on a 0-100 scale and their emotional and moral responses.
It appeared that the more threat or outrage they felt toward
crime type, the more likely they were to find the defendant guilty.
The authors also tested different types of evidence’s
potential interaction with people’s beliefs.
They found that both DNA and non-DNA physical evidence had
the highest amount of influence on participants, but the difference between how
the participants weighed them was small. The jurors appeared to place very
similar, if not the same amount of weight onto these two types of evidence in
terms of their confidence.
Pearson refers to juror’s equal weight of DNA and non DNA
evidence as the “CSI effect.” But DNA evidence is far more reliable than non
DNA evidence. The CSI effect lays out that jurors tend to give more weight to
conclusions based on traditional evidence. The study found that no matter one’s
position, the pattern of similar weight between the DNA and non DNA evidence
was found across all groups. The study also states that “subjects tend to
overweight widely used types of forensic evidence, but give much less weight
than expected to a defendant’s criminal history.”
Along with finding similar patterns between confidence in
guilt and evidence type, researchers also discovered an intense link between
the subject’s confidence in guilt with the severity of the crime.
Notably for jurors, crime type highly influenced their
perception of confidence in guilt. The study showed a positive correlation
between personal, emotional, and moral biases and “adjudicative bias,’ or the
likelihood of conviction.
And while jurors did show more of a trend in this finding,
practicing lawyers and prosecutors also exhibited a crime-type bias correlation
with the seriousness of crime, even though it was much smaller.
The study’s results model how punishment, outrage, and
threat are almost entirely dependent on crime effect and crime scenario. This
indicates that despite how much evidence was presented, crime type alone
influenced jurors decisions to charge someone as guilty of that crime more
This could mean that regardless of how much evidence or what type of evidence is present, innocent people wrongly charged of crimes could more easily be convicted if it is a more severe offense.
These findings indicate how easy it is to reach wrongful convictions of severe crimes within the US criminal justice system.