Transcript Theories of Crime

Explanations of Criminal
Behavior
Theories of Criminal Behavior
Who commits crime?
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Brainstorm reasons for criminal behavior
based on these three catagories:
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Social
Economic
Biological
Other???
Theories of Criminal Behavior
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Biological Theories – genetic and physiological. Cause
is the individual, no real part played by social factors.
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Personality Theories – certain types inclined to crime
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Social Learning – learned criminal ways
Issue – Nature vs. Nurture debate
Old school theories………
Cesare Lombroso
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Lombroso in 1876 argued
that the criminal is a
separate species, a
species that is between
modern and primitive
humans. He argued that
the physical shape of the
head and face determined
the "born criminal".
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William Sheldon believed that body types
determined criminality.
1.
endomorphic (fat and soft) sociable and
relaxed.
ectomorphic (thin and fragile) are introverted
and restrained
Mesomorphic = CRIMINAL (muscular and
aggressive) tend to be aggressive and
adventurous.
Sheldon found that many convicts were
mesomorphic, and they were least likely to be
ectomorphic (Sheldon et al 1949).
2.
3.
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MODERN THEORIES
Neurophysiological
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Raine 1994 used PET scans to study the living
brains of impulsive killers. Damage was found in
the pre-frontal cortex, which controls impulsive
behavior.
Neurophysiological
PET Scanner
Neurophysiological
PET Scan
Neurochemical
The brain’s chemistry can be influenced by diet,
for example, food additives, pollution or
hypoglycaemia (low blood sugar levels
associated with forms of diabetes).
The TWINKIE DEFENSE: A murderer in
California claimed that the sugar in Twinkies
caused him to become homicidal.
Neurochemical
STEROIDS? Individuals who take large amounts
of steroids can become extremely violent
(known as "roid rage"). Steroids, usually taken to
increase muscle growth, also increase
testosterone levels. However a direct link
between steroids and violence has not been
made.
http://www.youtube.com/watch?v=hN7rf4Mm1QA
Family Studies
Nature vs.
Nurture
debate
Twin studies: Genetic influence
on crime
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IDENTICAL TWINS (same genes and gender) that have
been separated at birth and brought up separately have
been studied
The degree of similarity between two twins is known as
the concordance rate.
This rate was compared with FRATERNAL twins who
are brought up separately
Looking at a number of studies the average
concordance rate is 55% for IDENTICAL twins and 17%
for FRATERNAL twins (Bartol, 1999).
Psychopathy or Sociopathy?
Psycho
or Weirdo?
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PSYCHOPATHS (NATURE)
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Psychologists use the term psychopathy to describe a psychological disorder that is
the product of a combination of
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psychological,
biological,
genetic and,
to a lesser degree environmental factors.
Studies have shown that psychopaths have inherent temperamental differences such
as
 impulsivity,
 fearlessness, and
 reduced physiological responsiveness
resulting in a high level of risk-seeking behavior and lack of adherence to social
norms.
Recent research has demonstrated that early signs predictive of psychopathy can
be present at a very young age (Viding 2005, Glenn 2007).
Sociopathy
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Sociopaths (Nurture)
Sociologists typically prefer the term sociopath.
sociopaths possess:
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reasonably normal temperaments; their social pathology more a
result of negative sociological factors such as parental neglect,
running with the wrong crowd, poverty, and extremely low or
extremely high intelligence(Lykken 1995).
Although all personality disorders are likely to be the
result of some level of interaction between genetic
predispositions and environmental factors, according to
these definitions, psychopathy is defined primarily by
hereditary and sociopathy by environmental influences.
Adoption studies
A study looked at court convictions in a small European country
and found 14,000 adoptees amongst them.
The criminal records of their biological and adoptive parents were
then investigated. Many of the adoptees had criminal biological
parents (particularly strong relationship for sons and fathers).
There was no relationship in the types of crime committed.
HOWEVER: Where there was an improvement in social
conditions by adoptive parents there was a reduction in crime
(going against the genetic explanation).