Rupert Macey-Dare (St Cross College - University of Oxford; Middle Temple; Minerva Chambers) has posted Unsafe Convictions and High Miscarriage of Justice Risk in Scottish Criminal Law Trials? Not Guilty, Not Proven, Or Guilty as Charged? on SSRN. Here is the abstract:
Scottish High Court criminal trials, have 2 unusual attributes. Firstly individual jurors and juries can vote Not Proven as an acquittal alternative to Guilty or Not Guilty. Secondly a majority Guilty verdict can be delivered by an 8-person majority from a jury as large as 15-strong.
This paper uses a simple mathematical model below to consider 2 related questions. Firstly, is a Not Proven jury vote or verdict a valuable additional option per se? Secondly, how safe and how high is the unsafe conviction and miscarriage of justice risk that could flow from such cases in Scotland?
Viewed in isolation the Not Proven juror and jury vote option is shown to be potentially highly valuable, because it essentially doubles the amount and precision of feedback information from any juror or jury who do not vote Guilty, to all parties including the judge. So in an ideal world without undue inertia and attachment to tradition there would be a good argument for adding in the Not Proven verdict as an additional alternative for juries in standard criminal law jurisdictions that apply the Beyond Reasonable Doubt test, e.g. as in England & Wales, USA, Canada, Australia, New Zealand etc.
However paradoxically this Scottish Not Proven option can allow some Scottish law criminal Guilty convictions to be decided with very low average probability of Guilt barely above the civil Balance of Probability Threshold e.g. for a 15-person jury with 8 jurors voting Guilty and 7 jurors voting Not Guilty (as opposed to either Guilty or Not Proven). On reflection, this should not really be at all surprising, because a bare Scottish majority Guilty decision is effectively just a Balance of Probability of Guilty Votes test.
This leads to the dramatic conclusion that the current Scottish criminal court jury system verdict acceptance rules may be fundamentally flawed and not fit for purpose, because the current risks of unsafe convictions and miscarriage of justice are likely to be far too high.
The paper then estimates how high under an adjusted system a majority decision would be needed for reasonably high safety and low enough miscarriage of justice risk in such cases. The adjusted estimates are 14* Guilty to 1* Not Guilty, or 12-15* for Guilty and 3-0* for Not Proven, so a very significant adjustment clearly needed from where Scots criminal law conviction threshold is currently set today.
Finally proposed changes in the expected: “Victims, Witnesses and Justice Reform (Scotland) Bill” to increase the required juror majority to 2/3 for a valid Guilty verdict, to reduce jury size from 15 to 12, and to remove the Not Proven verdict option, are analysed and shown to have likely mixed impacts, partially improving verdict soundness and partially reducing residual miscarriage of justice risk from future Scottish jury Guilty verdicts, so arguably taking net steps in the right direction.
