The strength of a Longman direction must be proportionate to the circumstances, including the length of delay: gross delays of many years require strong warnings, while shorter delays in factually narrow cases may be adequately addressed by less emphatic directions. The requirement that a direction bear 'the weight and authority of the court' means only that the jury must understand the warning comes from the judge, not counsel — no particular form of words is required. It is undesirable to use the phrase 'dangerous to convict'.
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