In the late eighteenth century a number of studies were carried out by morphology. Lombrosso studied the shape and structure of the human head. He believed that there was a link between the shape of the skull and the structure of the brain that it contained; suggesting certain abnormalities in the skull could be related to criminal behaviours. He measured the facial features of prisoners in Italian jails and identified physical characteristics, that he believed indicated criminality. Individuals that had these features were considered to be a more different type of human being.
Among the features which Lombroso identified were the following: an over-sized brain, squinting eyes, prominent eye-brows and a projecting jaw. According to Lombroso' findings these particular types of human beings found it difficult to adjust socially to civilised society. However it can be argued that the experiments that Lombroso carried were not valid as he did not compare his criminal sample to a non-criminal control group or take account of racial and ethical differences. Furthermore his measurements were inaccurate as he did not use appropriate statistical techniques and he did not have accurate understanding human physique.
In addition to this it can be that that identifying criminals by their physical characteristics can cause stereotyping and prejudice as people have been labelled to this theory. Bandura et al. (1963) did an experiment into children learning aggression. He divided up 66 nursery school children into three groups. All three groups watched a film where an adult kicked and punched a Bobo doll. In group 1 the children saw the Bobo doll being beaten by an adult. In group 2 children saw an adult telling off the Bobo doll in an aggressive behaviour and in group 3 the Bobo doll was neither beaten nor punished the Bobo doll.
The children were then allowed to play in the room with the Bobo doll whilst experimenters watched through a one-way mirror. Results showed that children in group 1 behaved most aggressively. In group 2 the children behaved least aggressively so this also gives Bandura positive results for his theory, as some children did not act violently towards the Bobo Doll as they observed the adult getting told off for hitting it. As this theory is reliable, the testing was also fair as all the children were put in the same room.
This shows that the television is a powerful source of imitative learning and that children may use television models as a source of use that act as a guide for their own behaviour. However in the other hand the theory has its problems such as the children participating may not have been the same age, Their backgrounds were not taken into account which makes the test unfair as some of the children may be from rough areas where fighting is common and some may be from none violent areas where violence haven't been used or seen so therefore they will behave differently.
8 months later 40% of the children were put back in the same room as the Bobo doll was in, as they were still violent to the doll. The Bobo doll is also not a living person so the children may react more violently as they know they are not inflicting any pain. Children can learn how to become a criminal by looking at a role model. If the role model is good then the children will be could and never been tough in a way to harm a thing. But if the role model is a criminal then the children would copy the role model of the criminal.
Aggression of behaviour can be found in criminals. This behaviour can be something that they born with or they learnt by. In the Bandura study we see that children can learn aggressiveness by looking at role models for example movie stars who might come in action films or aggressive sports. In the study an adult was aggressive toward a Bobo doll, the children were then observed to see if they imitated any behaviour shown by the model, or if they were not aggressive.
There were also 2 other groups, one of which had seen a non aggressive by physical contact but in verbal aggressive from the adult and another group was observed after seeing no adult therefore no verbal or physical were not taken in action of the Bobo doll. Results showed that the first group the children behaved most aggressively by seeing the video of the adult physically abusing the doll. But in the second group the children behaved least aggressively, as the children was shown in the video of the adult verbally abusing the Bobo doll but not giving physical abuse.
Overall what he had found is that observing of an adult is enough for aggressive behaviour to be learned. Much of Bandura's work was focused on observational learning of aggressive behaviour, but does not lead into criminality. It has however, been used to advance differential association theory, which does lend itself to criminality. Some will say that a person who would have a lot of testosterone is born this way and be more aggressive. However some other people would say that other people with testosterone aren't aggressive.
People who born with XYY chromosomes are more likely to be aggressive because they are more in the jails. But it might be that lots of male are out of jail are XYY but they are not in jail. In the theory of the XYY chromosomes a normal human cells contain 46 chromosomes. Individuals receive half their chromosomes from each parent and in this way genetic transmission occurs. One particular pairing of chromosomes determines sex e. g. female XX, male XY.
Some individuals have abnormal chromosomal combinations, and if the presence of an extra Y chromosome in males is created, as this make the person aggressive and violent. However there is no evidence that the vast majority of criminals have this or any other chromosomal abnormality. Some criminals would have an extra Y chromosome and may carry a slightly higher risk of behavioural problems but not all people with this abnormality will be criminals and not all criminals born with XYY chromosome. But this could be found in only account for predisposition in a small percentage of criminals.