Reading Biological
Explanation
The Biological Basis of Criminal
Behavior
Bonta, J., & Andrews D.A. (2016)
Biological factors lie at the base of criminal behaviors
Consistent finding from developmental criminology ⇒
most youths
(especially males) engage in various antisocial acts as they grow
into adulthood, but they follow different trajectories
1. adolescent-limited
2. life-course-persistent
mostly males
start behaving antisocially early
often escalating in the seriousness of their acts
5-10% of offenders
commit majority of crime
Crime Gene
Jacobs et al.(1965) ⇒ suggested a link between an extra Y chromosome
and violent behavior
however, well-designed epidemiological studies found that having
an extra Y chromosome was largely irrelevant
Three studies followed up;
they found that XYY men had more criminal convictions than XY men
they found no differences in criminal offending between XYY and
XXY men
Reading Biological Explanation 1
, Longitudinal study XXY children, Geerts, et al.(2023) ⇒ half of the
38 boys evidenced psychosocial problems
but childhood autism was a more likely outcome than conduct
disorder
💡 The XYY falls into the trap of oversimplification and genetic
determinism (no strong link)
Intergenerational Crime
Today, there is evidence of intergenerational criminality
this applies equally to boys and girls
found across three generations
Having a criminal father was the best predictor of the son’s
involvement in delinquency
social difficulties (e.g. low family income) also predicted
delinquency
these social indicators predicted better for officially
recorder delinquency than for self-reported
Assortative mating = when individuals mate with similar individuals
Farrington et al.(1996) ⇒ 83% of boys grew up and married women who
also had criminal records
Farrington et al.(2007) ⇒
found that family criminality was the best
predictor of antisocial behavior for any family member
💡 Criminal behavior can be passed through generations, but
environmental factors like assertive mating and family dysfunction
play a significant role
Reading Biological Explanation 2
, Twin Studies
Lange (1929) ⇒
concordance rate for MZ twins with respect to
criminality (77%) was higher than with DZ twins (12%)
serious methodological problems
Christiansen (1977) ⇒ concordance rate for MZ twins was 35% and for
DZ twins 12%
As twin studies became more methodologically sophisticated, the
concordance rate for MZ twins dropped to 26%
there is a moderate relationship between heredity and antisocial
behavior
Grove et al.(1990) ⇒ MZ twins were followed into adulthood, the
concordance rate for antisocial personality disorder was 29%
Gaspi et al.(2004) ⇒ tried to answer the question; do mothers
genetically transmit hostility to the children or does the aggressive
behavior of the child produce a hostile reaction from the mother?
mothers did not treat each twin similarly
one twin would be described positively and the other negatively
negative emotions expressed by the mother predicted aggression in
their child (rated by teacher)
The researchers concluded that it was the mother’s treatment and
not heredity that explained the child’s aggressiveness
💡 Heredity plays a role in antisocial behavior, but environmental
factors, such as maternal treatment and family dynamics, are crucial
factors
Adoption Studies
Reading Biological Explanation 3
, In adoption studies, the criminal futures of adopted children are
analyzed in relation to;
criminal history of the biological parents
criminal history of adoptive parents
particular combinations in the biological and adoptive parents
Mednick et al.(1984) ⇒ found a
very small genetic effect (r =
.3)
adoptees raised by
noncriminal parents, but who
had criminal biological
parents, were at higher risk
of being convicted than
those with both noncriminal
parents
Follow-up investigation (1987)
⇒ as the number of convictions
for the biological parents went
up, so did the number for the
adoptees
Parental criminality by itself appeared insufficient to explaining
violent crime in the offspring
Carey & Goldman (1997) ⇒ found that all six adoption studies showed
a genetic effect
Meta-analyses (1997+2002) ⇒ the concordance rate for the adoption
studies decreased significantly
but is was not zero
Barnes et al.(2014) found a correlation between genetic and
criminal variables from 0.30 to 0.60
Malouff et al.(2008) ⇒ found higher heritability was associated with
the severity of the problem
Reading Biological Explanation 4
Explanation
The Biological Basis of Criminal
Behavior
Bonta, J., & Andrews D.A. (2016)
Biological factors lie at the base of criminal behaviors
Consistent finding from developmental criminology ⇒
most youths
(especially males) engage in various antisocial acts as they grow
into adulthood, but they follow different trajectories
1. adolescent-limited
2. life-course-persistent
mostly males
start behaving antisocially early
often escalating in the seriousness of their acts
5-10% of offenders
commit majority of crime
Crime Gene
Jacobs et al.(1965) ⇒ suggested a link between an extra Y chromosome
and violent behavior
however, well-designed epidemiological studies found that having
an extra Y chromosome was largely irrelevant
Three studies followed up;
they found that XYY men had more criminal convictions than XY men
they found no differences in criminal offending between XYY and
XXY men
Reading Biological Explanation 1
, Longitudinal study XXY children, Geerts, et al.(2023) ⇒ half of the
38 boys evidenced psychosocial problems
but childhood autism was a more likely outcome than conduct
disorder
💡 The XYY falls into the trap of oversimplification and genetic
determinism (no strong link)
Intergenerational Crime
Today, there is evidence of intergenerational criminality
this applies equally to boys and girls
found across three generations
Having a criminal father was the best predictor of the son’s
involvement in delinquency
social difficulties (e.g. low family income) also predicted
delinquency
these social indicators predicted better for officially
recorder delinquency than for self-reported
Assortative mating = when individuals mate with similar individuals
Farrington et al.(1996) ⇒ 83% of boys grew up and married women who
also had criminal records
Farrington et al.(2007) ⇒
found that family criminality was the best
predictor of antisocial behavior for any family member
💡 Criminal behavior can be passed through generations, but
environmental factors like assertive mating and family dysfunction
play a significant role
Reading Biological Explanation 2
, Twin Studies
Lange (1929) ⇒
concordance rate for MZ twins with respect to
criminality (77%) was higher than with DZ twins (12%)
serious methodological problems
Christiansen (1977) ⇒ concordance rate for MZ twins was 35% and for
DZ twins 12%
As twin studies became more methodologically sophisticated, the
concordance rate for MZ twins dropped to 26%
there is a moderate relationship between heredity and antisocial
behavior
Grove et al.(1990) ⇒ MZ twins were followed into adulthood, the
concordance rate for antisocial personality disorder was 29%
Gaspi et al.(2004) ⇒ tried to answer the question; do mothers
genetically transmit hostility to the children or does the aggressive
behavior of the child produce a hostile reaction from the mother?
mothers did not treat each twin similarly
one twin would be described positively and the other negatively
negative emotions expressed by the mother predicted aggression in
their child (rated by teacher)
The researchers concluded that it was the mother’s treatment and
not heredity that explained the child’s aggressiveness
💡 Heredity plays a role in antisocial behavior, but environmental
factors, such as maternal treatment and family dynamics, are crucial
factors
Adoption Studies
Reading Biological Explanation 3
, In adoption studies, the criminal futures of adopted children are
analyzed in relation to;
criminal history of the biological parents
criminal history of adoptive parents
particular combinations in the biological and adoptive parents
Mednick et al.(1984) ⇒ found a
very small genetic effect (r =
.3)
adoptees raised by
noncriminal parents, but who
had criminal biological
parents, were at higher risk
of being convicted than
those with both noncriminal
parents
Follow-up investigation (1987)
⇒ as the number of convictions
for the biological parents went
up, so did the number for the
adoptees
Parental criminality by itself appeared insufficient to explaining
violent crime in the offspring
Carey & Goldman (1997) ⇒ found that all six adoption studies showed
a genetic effect
Meta-analyses (1997+2002) ⇒ the concordance rate for the adoption
studies decreased significantly
but is was not zero
Barnes et al.(2014) found a correlation between genetic and
criminal variables from 0.30 to 0.60
Malouff et al.(2008) ⇒ found higher heritability was associated with
the severity of the problem
Reading Biological Explanation 4
