Juvenile Delinquency 83praising as there is, can be irregular. A lack of techniques for dealing
with family crises and problems means that conflict leads to ongoing
tension and disputes. Physical, emotional and sexual child abuse are not
uncommon.Individual factors
Behaviour. Around 90% of recidivist delinquents were antisocial enough
to meet criteria for conduct disorder in middle childhood. Thus, the
notion that the majority of this persistently delinquent group were fine
initially but then ‘fell in with a bad crowd’ in adolescence is a myth. On
the other hand, the majority of one-time offenders have unremarkable
earlier histories – it is indeed often part of ‘a phase teenagers commonly
go through’. However, repeaters who only start in adolescence do not
necessarily stop in early adulthood – half continue low-level offending.
Intelligence. There is a fairly strong association between lower IQ and
greater delinquency. Thus, in one study, 20% of youths with an IQ
of less than 90 were recidivist, as opposed to 2% of youths with an
IQ of 110 or more. Self-report figures show the association between
delinquency and low IQ is not simply due to brighter delinquents
escaping detection. Perhaps the link between low IQ and delinquency
is mediated by educational failure, poor self-esteem and frustration.
Alternatively, low IQ may simply be a marker for other biological or
social disadvantages. It is interesting that the link between low IQ and
conduct problems has been found at as young an age as 3 years old.
Biology. The general genetic contribution to adult criminality has al-
ready been mentioned. By comparison with controls, adult criminals
have been shown to have less autonomic reactivity to stress, impaired
passive avoidance learning, greater aggression, poorer attention skills
and a greater tendency to seek thrills. Whether these characteristics are
acquired or inherited is unclear. Offending is only rarely attributable
to specific organic syndromes. Though EEG studies of delinquents do
not show any consistent abnormalities, seriously aggressive outbursts
are sometimes attributed to an ‘episodic dyscontrol syndrome’, perhaps
linked to temporal lobe pathology and complex partial seizures. The
XYY chromosome anomaly is not associated with an increase in violent
crime, but does seem to be associated with an excess of petty criminality,
perhaps mediated by the link with low intelligence.
Relationships. Juvenile delinquents are more likely than non-delinquents
to have impaired and disharmonious relationships with same-sex peers
and with members of the opposite sex. The greater part of juvenile
delinquency is committed with other antisocial peers, and there is
abundant evidence that associating with them increases the likelihood
of persistence of criminal behaviour. As discussed below, this means that
intervention programmes and prisons that put antisocial youths together
without very close control of what they say and do may well be actively
harmful. Lifetime studies of delinquents in 1950s America showed that