Andrew Stevenson

Andrew Stevenson, secretary of SLAS, said the organisation’s council supports retention of the verdict because it is “logical”.

“The feeling was that if any verdict should be abolished it should be ‘not guilty’, with the court making a finding or ‘proven’ or ‘not proven’. That is a more logical choice given that the court itself is not being asked to determine anyone’s innocence; that arises instead from a legal presumption,” he said.

Professors James Chalmers, Fiona Leverick and Vanessa Munro state in an article on the history of the verdict that the argument from logic is “a tiresome feature of much of the debate” as different logical premises are employed by supporters and detractors.

Mr Stevenson added: “Historically, the ‘not proven’ verdict was most notoriously associated with poisoning cases, but in modern times it seems to be blamed for the high incidence of acquittal in prosecutions for rape.

“However, some critics of the verdict overlook the fact that without it any court which found that the Crown had not proved its case would have to return a verdict of ‘not guilty’.

“Would that be of any consolation to a complainer who maintained that she had in truth been the victim of an acquitted accused person?”

Mr Stevenson pointed to the case of Stephen Coxen in 2015, against whom a rape charge was found to be not proven.

“Three years later he was found by the All Scotland Personal Injury Court to have raped his victim. Without the third verdict, Coxen would logically have been found not guilty after trial. That would surely have been worse than ‘not proven’.”

He added that it would be difficult to find out whether the verdict was responsible for any miscarriages of justice.

“The confidentiality of a jury’s deliberations is protected by the Contempt of Court Act, and research has had to be on mock juries instead, or on anecdotes.”

He concluded: “Removing the third verdict is prejudicial to the accused person to the extent that a re-evaluation of the whole structures of juries would be needed, with consideration having to be given to scrapping the sufficiency of a simple majority.

“Presumably if a majority of, say, 13 were necessary there would be fewer convictions than at present. One can assume that this is not the consequence intended by detractors of the not proven verdict.

“The system as it stands has worked satisfactorily for centuries, and should be retained.”