Scotland’s ‘not proven’ verdict, the 15 person jury and the ability to convict or acquit an accused by a simple majority could all face reform, when a major study of juries is published this week.

The findings of the research are expected to lead to a consultation on whether to scrap the ‘third’ verdict, leaving juries the option of just guilty or not guilty. Ministers have been pressed to drop the ‘not proven’ option, notoriously described by Sir Walter Scott as ‘that bastard verdict’. The then Scottish justice Secretary Michael Matheson commissioned the research from Glasgow and Warwick universities two years ago in response to recommendations made by Lord Bonomy in a review of the safeguards needed if corroboration were to be scrapped.

It has seen hundreds of members of the public serving on mock juries, and has taken evidence from more than 1000 jurors, in one of the biggest enquiries into the jury system ever in the UK.

The findings are believed to include a recommendation that the Government consider reducing the size of juries in Scotland and introducing a more demanding criteria for delivering a verdict. In Scottish courts a verdict can be achieved by a simple majority of jurors, whereas in England the minimum requirement is 10, with no more than two dissenters.