2. Research has been carried out to discover whether criminal tendencies can be inherited - Does crime run in families? Dugdale’s (1910) study of the Dukes family and Goddard's (1914) study of the Kallikaks, claimed this was so by looking at family trees of criminals These studies can be criticised because of their lack of methodological rigour and are now largely discredited as anecdotal. Dukes: In 1874, sociologist Richard L. Dugdale, a member of the executive committee of the Prison Association of New York, was delegated to visit jails in upstate New York. In a jail in Ulster County he found six members of the same "Juke" family (a pseudonym), though they were using four different family names. On investigation, he found that of 29 male "immediate blood relations", 17 had been arrested and 15 convicted of crimes.

4. A consistent finding in their research is that criminal parents are more likely to have criminal children...!!! Osborn and West (1979) found that 40% of the sons of criminal fathers had criminal convictions, compared with a figure of 13% for the sons of non-criminal fathers, but it should be noted that 60% of the sons of criminal fathers did not turn to crime!

5. Correlation dose not imply causality and being born into a criminal family is not a necessary condition for criminal behaviour Another variable which family members share e.g. Poverty or parenting styles might account for the criminal behaviour.

7. MZ & DZ Twins DZ twins are non-identical; MZ are identical. MZ twins are more alike as there genetic make-up is very similar and therefore if they are a particular build, they may attract more social interpretation as being criminals. DZ twins aren’t identical and could be the opposite because one twin could be a particular build whereas the other twin could be different.

8. Christiansen, 1977 Suggested that any similarities between twin pairs can be distinguished as the result of genetic or environmental influences. Found that MZ twins appear to share more criminal tendencies than DZ twins. It has been argued that this demonstrates a significant genetic component in criminal behaviour.

9. When twins are studied, psychologists measure the differences of behaviour and characteristics by “Concordance” which is the degree to which twins display the same behaviour and characteristics. Concordance is usually expressed as a percentage, so for example a 100% concordance would indicate that in every studied pair, both twins possessed the same characteristics. 50% would indicate that half of the total sample both twin pairs displayed the same behaviour.

10. Below is a table of studies which have indicated a concordance rating between twins: ResearcherMZDZ Lange7712 Kranz6553 Yoshimasu500 Christiansen6030 These studies suggest that there is a relationship between genes & criminal behaviour- however, if it was purely genetic then we would expect 100% concordance Monozygotic: identical Diyzygotic : from two different eggs

16. Neuropsychology, one of the most controversial developments in the search for a biological basis on criminal behaviour, was one of the uses behind theories for a criminal’s action. For example, in 1966 Charles Whitman killed 21 people in the time of one day. An autopsy of Whitman revealed a large brain tumour which could have been affecting the amygdala, the part of the brain responsible for controlling aggressive urges. Such serious brain injuries could be the cause for a dramatic change in personality and behavioural changes.

17. Antisocial behaviour is also believed to be partly contributed thanks to neurological disorders, development co-ordination disorder (the sufferer’s clumsy, forgetful) or dyspraxia. These disorders can lead to sufferers becoming accident-prone, unco- ordinated and unpopular. Thus leading to criminal activity. Although these theories seem believable and attractive. Serious problems could lie ahead for young children for example, who’d be labelled as potential criminals. One of the problems with this biological determinism is that the theory fails to take into account the actual complexity of criminal behaviour and how it can be socially constructed.