Acquittals are final, even if they might be based on flawed reasoning: McElrath v Georgia 22-721 USSC (21 February 2024). [1]
Authorities referred to in this case make the following points. An acquittal by a jury ends a defendant’s jeopardy. A jury’s verdict of acquittal cannot be reviewed and this is the most fundamental aspect of double jeopardy jurisprudence. An acquittal is a ruling that the prosecution’s proof is insufficient to establish criminal liability. A jury’s verdict of not guilty on the grounds of insanity is such a ruling. It does not matter if this verdict is accompanied by an apparently inconsistent verdict on another charge; an acquittal is still an acquittal. Any judicial speculation about the jury’s reasons for a verdict of acquittal would impermissably usurp the jury’s right to have its deliberations free from such scrutiny. This remains so, while it has long been recognized that a jury’s verdict may be the result of compromise, compassion, lenity, or misunderstanding of the law. The inviolability of a jury’s verdict of acquittal is a bright-line rule that exists to preserve the jury’s overriding responsibility to stand between the accused and those who command the criminal sanction.
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[1] There can be statutory exceptions to the finality of acquittals. For example, see the Criminal Code of Canada, s 686(4). Acquittals are not lightly overturned under this provision: R v Sutton, 2000 SCC 50, and see R v Khill, 2021 SCC 37. In New Zealand an appeal on a question of law does not include a question that arose from a jury verdict, Criminal Procedure Act 2011, s 296(4)(a).
