Evidence of Bad Character in Criminal ... - Law Commission

6.36 Some argued that we must trust juries because we have them. We are
unpersuaded by this argument. It seems to us that the crucial question is whether
there is any foundation for such trust. The best way of determining this is through
empirical research; yet few of the respondents who argued for greater openness
referred to the empirical studies discussed in the consultation paper.
THE RESEARCH
6.37 Dr Lloyd-Bostock’s research on the effect of bad character evidence on mock
jurors, which we summarised in the consultation paper, found that a conviction
was more likely to result if the jury were told that the defendant had either a
recent conviction for an offence similar to that charged or one for indecent
assault on a child (irrespective of the offence charged). The former tendency may
well be explicable on the basis that it is entirely rational to attach probative weight
to a recent similar conviction. However, it is hard to see any rational basis for the
latter phenomenon, which would appear to be based on prejudice alone. 29
6.38 This conclusion seems to be supported by the experience of respondents. Even
those who had faith in juries found that that faith deserted them when it came to
sexual offences. One QC wrote that “it is insulting to juries to assume they
cannot be trusted properly to evaluate the worth of previous convictions”; yet he
was unsurprised by the results of the Jury Study, explaining that “Any criminal
hack could have told you that he was terrified of letting his client’s character in
whatever the nature of the offence where it included [a conviction for indecent
assault on a child].”
6.39 Several respondents emphasised the limitations of the research. The most
frequent observation was that a mock jury is no substitute for the real thing, and
that the results should therefore be treated with circumspection. We
acknowledged and emphasised the limitations of the research in the consultation
paper, 30 and accept that studies on real jurors might produce different results.
However, given that such research as has been done does reveal a risk of
prejudice, we do not accept that we would be justified in asserting that there is
no risk of prejudice to real defendants in real trials: we could only do that on the
basis of research into real juries.
6.40 Moreover, the results of the Jury Study can now be compared with Dr Lloyd-
Bostock’s more recent research, which, being concerned with real magistrates, is
not open to the same objection. It was found that magistrates tend to regard a
disclosed earlier. We note that, in France, where the defendant’s record does form part of
material on which the verdict is founded, a trained judge sits with the lay fact-finders. Both
fact-finders and judge deliberate on guilt and sentence (see pp 593–594). See also
A Zuckerman, The Principles of Criminal Evidence (1989) p 245.
29 There was a further tendency to regard a defendant as less likely to have committed the
offence charged if he had a recent conviction for a dissimilar offence (unless it was for
indecent assault on a child). This may be explicable, but strongly suggests an element of
irrationality in the reasoning process.
30 Paras D.54 – D.59.
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