Children who bully at school
Childhood development and criminal offending later in life
Children who bully tend to have a wide array of behaviour and emotional problems. Comorbidity or the co-occurrence of bullying and other childhood disorders is common.
Children's developmental problems
Children who bully display more conduct problems and other externalising behaviours (see Box 3; Cook et al., 2010; Salmon, James, Cassidy, & Javaloyes, 2000). They have been found to be impulsive and lack self-control (O'Brennen et al., 2009; Pontzer, 2010; Unnever & Cornell, 2009). They are more likely to be inattentive and hyperactive (Cho, Henderickson, & Mock, 2009). Coolidge, DenBoer, and Segal (2004) found bullying behaviour to be associated with diagnoses of conduct disorder, oppositional defiant disorder, attention-deficit/hyperactivity disorder, and depressive disorder compared to a group-matched control group. A positive attitude toward aggression, combined with impulsivity, has also been found to increase the likelihood that children will behave aggressively (Fite, Goodnight, Bates, Dodge, & Petit, 2008).
Various psychiatric correlates have also been identified. Children involved in bullying at the age of 8 or 12 years - in particular those who were bully victims - were reported to have more psychiatric symptoms and a greater chance of displaying deviant behaviour when they reached 15 years (Kumpulainen, Rasanen, & Puura, 2001). Some studiesindicate that anxiety and depression are equally common among bullies and victims (e.g., Kaltiala-Heino, Rimpelä, Rantanen, & Rimpelä, 2000).
Box 3: Behavioural and emotional problems associated with childhood bullying
- Bipolar disorder
- Lifelong alcohol and marijuana use
- Nicotine dependence
- Antisocial personality disorder (characterised by a pervasive pattern of disregard for and violation of the rights of others, and a lack of empathy)
- Paranoid personality disorder (characterised by a pattern of irrational suspicion and mistrust of others, interpreting motivations as malevolent)
- Histrionic personality disorder (characterised by a pervasive pattern of attention-seeking behaviour and excessive emotions)
- Passive-aggressive disorders
- A family history of antisocial behaviour
Source: Vaughn et al. (2010)
Criminal offending as an adult
There is now strong evidence for a substantial link between children who bully their peers and later offending and depression. Bullying others at school is a highly significant predictor of a child growing up to be a criminal offender, on average six years later in life. Farrington, Lösel, Ttofi and Theodorakis (2012) have provided the most comprehensive and up-to-date scientific evidence on this. Using meta-analyses, the authors specifically looked at the strength of the relationship of school bullying with later offending and depression, using the findings reported from longitudinal studies (29 associated with offending and 49 associated with depression), including Australian studies. Their research suggests that bullying peers at school increases by more than half the risk of later becoming an offender. Bullying peers at school was also significantly related to later depression - increasing the risk by 30%.
An additional body of research has isolated bullying as a unique risk marker of later offending. For example, the Christchurch Health and Development Study, a longitudinal New Zealand study spanning 30 years, provided evidence for direct linkages between childhood bullying and violent offending and arrest/conviction in adulthood, independent of the effects of childhood conduct and attention problems (Fergusson, Boden, & Horwood, 2014). In an Australian longitudinal study of 650 adolescents (in Victoria), students who bullied at age 16-17 years had over four times the odds of engaging in non-violent antisocial behaviour and two times the odds of violent antisocial behaviour in young adulthood (age 19-20 years) (Hemphill, Tollit, & Herrenkohl, 2014). Similarly, longitudinal data from the Edinburgh Study of Youth Transitions and Crime, a prospective cohort study of around 4,300 young people in Scotland, found that those who engaged in persistent bullying in their early teens (ages 13, 14, 15, and 16 years) were at increased risk of being violent in later adolescence (age 17 years) (McVie, 2014). Other prospective studies, such as the Cambridge Study in Delinquent Development (Farrington, 1993), point to inter-generational continuity - with those who had been bullies at age 14 being more likely at age 32 to have children who also bullied their peers.
Did you know?
Children who bully are more likely to:
- do poorly in school;
- turn to violence as a way to deal with problems;
- damage property or steal;
- abuse drugs or alcohol; and
- get in trouble with the law.