Safeguards against wrongful conviction
Scots law contains a requirement for corroboration, requiring two sources of evidence in support of every ‘crucial fact’ in a criminal trial. In 2012, the Scottish Government proposed to abolish the corroboration requirement. UofG research persuaded the Government to put its proposal on hold until additional safeguards against wrongful conviction—such as reform of the jury system—had been identified.
The research
A 2010-11 review, led by High Court judge Lord Carloway, recommended reforms to Scots law, including the abolition of the corroboration requirement.
Professor James Chalmers and Professor Fiona Leverick drew on their expertise in criminal procedure to write a critical evaluation of the Carloway proposals.
They warned that removing the corroboration requirement without replacing it with alternative measures would risk the Scottish criminal justice system lacking safeguards to protect against wrongful conviction.
This led to further research into jury reasoning and decision making to inform future decisions. Chalmers and Leverick were part of the team that carried out this research commissioned by the Scottish Government in 2017, which included the largest mock jury experiment ever conducted in the UK, involving a total of 64 mock juries.
The impact
The proposal to abolish the corroboration requirement was taken forward by the Scottish Government in the Criminal Justice (Scotland) Bill introduced on 20 June 2013.
The Bill was scrutinised by the Justice Committee in 2013-14 and Chalmers and Leverick’s research was referred to repeatedly during proceedings of the Committee when it took evidence from Lord Carloway.
Chalmers and Leverick also submitted written evidence and gave oral evidence to the Committee warning of the dangers of abolishing the corroboration requirement without alternative safeguards against wrongful conviction.
In 2014, the Committee drew on this evidence in recommending that the provision on corroboration be removed from the Bill—a recommendation followed by the Government.
The impact of retaining the corroboration rule is considerable. Corroboration is required in the vast majority of criminal cases progressing through the Scottish criminal justice system. This means it is applied in decisions on whether or not to prosecute taken in over 170,000 reports to the public prosecutor each year.
The next phase of the reform process involved an independent review into safeguards against wrongful conviction, which Chalmers and Leverick were extensively involved in.
This work will now inform a consultation on the not proven verdict, which opened in December 2021.