Download Biological theories

Biological Approaches
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Biological Approaches
Morphological
 Hereditary/Genetic
 Biochemical/neurophysiological
 Biosocial
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Morphological--Lombroso
Mophological approaches assume that
criminal behavior is inborn, associated
with physical body features, and that
criminals have body features which are
different from non-criminals
 Lombroso (late 1800s)
 Criminal behavior is atavistic in origin-reversion to a more primitive type
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Lombroso (continued)
Believed external body features are
associated with abnormalities of the
brain which result in criminal behavior
 Genetic accidents resulted in less than
fully evolved humans who had to live
among more modern men. Their
behavior was beyond their control
 “Born criminals” vs. “Criminaloids”
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Lombroso (continued)
Lombroso lacked adequate control
groups
 atavism does not exist in nature, there
are no such genetic accidents
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Sheldon’s morphological
research
Correlation between physique and
personality
 Endomorph
 Ectormorph
 Mesomorph
 Some research finds criminals are more
mesomorphic, slightly shorter and
lighter--why?
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Inheritance/genetic approach
Genes may be an indirect cause of
behavior by influencing structures and
functions that guide behavior
 Methods
 General pedigree studies (family studies
 Twin studies
 Cross fostering
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Family studies
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Jukes and the Kallikaks
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Twin studies
Identical twins vs. fraternal twins. vs.
siblings vs. unrelated children raised
together
 technique used to study intelligence,
criminality, mental illness, alcoholism
 condordance rates: rate of agreement
between pairs--if one has a trait does
the other have it?
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Adoption (cross-fostering)
Adopted children have two sets of
parents: biological, who supply the
genes, and adoptive, who supply the
environment
 Who determines whether the children
become criminal?
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Mednick’s study
In the table is the percentage of each
group who was arrested
Biological
YES
NO
Adoptive
YES 24%
14%
NO 20%
13%
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Conclusions
In all instances a minority committed
crimes. Other factors play a role.
 Biology played a role, in that children
who had parents who committed crimes
were more likely to commit crimes than
children who had not. It appears to
raise the probably, or risk, although in
all likelihood other factors are more
important
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XYY studies
It was hypothesized that an extra “Y”
chromosome would make a male more
aggressive, a “supermale”
 Richard Speck
 Karyotype studies
 2% of prisoners
 .1% to .2% in general population
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XYY (continued)
Therefore there are a greater
percentage in prison than in the general
population
 Most are not in for violent crimes
 Thus, not “super males”
 There may be sociological reasons
 The XYY defense has been
unsuccessful in court in the U.S.
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Neurochemical-physiological
Hormonal imbalances
 Diet (the “twinkie” defense)
 Toxic substances such as lead (related
to poverty)
 EEG abnormalities more common in
prisoners than in general population
 More birth problems, head injuries
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neurophysiological
Antisocial personality
autonomic nervous system
underarousal, less “flight or fight”
reaction
 need for stimulation
 less reaction to punishment
 poor performance in avoidance learning
 improved performance with adrenaline
injection
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Biosocial approach
physiological tendencies toward
criminality (such as being impulsive or
aggressive) may be acquired in different
ways
 The environment can act to encourage
or discourage criminality through its
interaction with the characteristics of the
individual
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Biosocial
Behavior results from interaction of
physiological and environmental factors
 People with certain factors will become
criminals if exposed to certain
environment
 People born into criminogenic
environments won’t become criminals if
they lack a physiological predisposition
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Gender and crime
Males are more likely to commit crimes
 All three crime measures agree
 UCR
violent--M:F 9:1

property M:F 4:1
 94% of U.S. prisoners are male
 Historical and cross cultural findings
support this
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Gender and crime
Lombroso: masculinity hypothesis
 Chivalry: treated more leniently
 Males are more likely to be denied bail
and to receive prison sentences rather
than probation
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Current thinking--2 perspectives
Biological and sociocultural
 Biological perspective
 Males are more aggressive than
females, and aggression and crime are
related
 There might be a biological basis for
differences in aggression
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Biological perspective
(continued)
Gender differences in aggressiveness
occur early in life, before sex-role
stereotyping of self
 Among other primates, males display
more aggressive behavior
 Differences in brain organization
 Males tend to be more aggressive,
dominant, visual-spatial
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Biological perspective
Females tend to have better language
skills
 Although there are differences, there is
considerable overlap, so some females
would commit crimes
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Sociological perspective (gender)
Women were discouraged from
competition
 Taught to be “ladylike”
 Supervised more closely
 Males and females are treated and
socialized differently
 Feminists have speculated that as the
role of women changed, more crime
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Socialization & gender
There has been some rise in female
crime, the reasons are unclear
 Female criminals come from the lowest
SES, least likely to benefit from the
changes that have occurred
 The rise might be due to the end of the
chivalry hypothesis
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