ABSTRACT
This chapter is concerned with a particular type of explanation, some preliminary warnings are necessary about the sort of explanations that are encountered in this field. It may be introspective, consisting of someone's beliefs about the circumstances or state of mind in which they have committed some delinquent act. Statistical Evidence becomes a statistical one as soon as an effort is made to ensure that cases studied are typical. The crudest way of doing so is to study such a large percentage of the individuals in which one is interested that the chances of the sample's being unrepresentative are small. Constitutional theories are those which assert that a substantial number of offenders are predisposed to behave in this way because of the physical or mental constitution with which they are born. The extent to which any two or more of these theories must be regarded as contradictory depends on whether they are asserted in the 'weak' or the 'strong' form.
