Murder and Serious Sexual Assault - Lancaster EPrints - Lancaster ...

SUMMARY AND CONCLUSIONS
previously had a conviction for burglary (which, of course, sounds quite a high
figure) unless it is known how the figure compares with similar persons who have
not murdered. The emphasis for this study was therefore a comparison with currently
active criminals.
Main findings
The results of the case-control approach have been presented in terms of relative
risk. Where high relative risk scores (above one) have been generated, they indicate
a greater likelihood of an event taking place if the risk factor is present. Low relative
risk scores (below one) indicate a lesser likelihood of the event taking place.
Following convention, these factors have been identified as significant when they
have been found to be statistically significant at the five per cent level. The vast
majority of the discussion has focused on ‘risk factors’ – those crimes that indicate a
greater likelihood of subsequent conviction for murder and SSA.
The major difference between offences which provide an increased relative risk of
being convicted of murder or SSA and those which provide a decreased relative risk
score is that for the former, around a half of the risk factors are ‘rare’ or ‘unusual’
offences, while the latter almost always fall within offence categories designated as
‘frequent’ or ‘sizeable’. What the analysis highlights is that the characteristics of the
general criminal population (who tend to thieve, commit burglary, shoplift, handle
stolen goods, steal vehicles, thieve from vehicles and get involved in drugs offences)
tend to lower the relative risk of getting involved in murder and SSA. However, we
have to be very careful in interpreting this point. Elsewhere (Soothill and Francis,
1999; Soothill, Francis, Sanderson and Ackerley, 2000) it has been found that a
high proportion of those convicted of sex offences are engaged in other kinds of
criminal activity. So, for example, while for the most prevalent offence – ‘other
theft’ – shows a significantly decreased risk of subsequent SSA convictions, it needs
to be remembered that almost exactly one-half (49.6%) of the SSA offenders still
had this offence in their prior criminal history. The finding does not suggest that
these offenders do not commit serious offences – they do. What it reveals however is
that, among the general criminal population, the more routine, high volume criminal
activity is not a good source for predicting future serious criminal activity.
In contrast, there are some comparatively unusual offences which, from the evidence
presented here, are better predictors of future convictions for murder or SSA (or
both). ‘Unusual’ offences were defined as those occurring in less than two per cent of
those convicted of murder or SSA. Therefore these particular offence characteristics
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