In Western Australia, the criteria in R v Goodwin (1990) 51 A Crim R 328 are appropriate to guide the discretion to admit evidence on a sentencing appeal that was in existence at the time of sentencing but not adduced, subject to a residual discretion to admit evidence in exceptional cases to avoid a miscarriage of justice. Where evidence was known to the applicant at sentencing, it will only be in an exceptional case that failure to disclose it will be found to have resulted in a miscarriage. Evidence of post-sentencing assistance to authorities is inadmissible unless it sheds new light on circumstances existing at the time of sentencing.
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