AN expert group has backed a radical shake-up of Scotland's legal system to prevent miscarriages of justice if controversial plans to scrap corroboration in trials go ahead.

Former High Court judge Lord Bonomy's high-powered panel has proposed far-reaching safeguards that would see historic features of Scots Law ditched along with the centuries-old requirement that two separate pieces of corroborating evidence are needed to prove guilt.

These include cutting the size of juries from 15 to an English-style 12 and the scrapping of majority verdicts where eight of 15 jurors agree.

Other preliminary proposals set out by the body include:

l Retaining the need for corroboration in those cases where a confession or hearsay evidence forms the basis of the Crown's case;

l Extending judges' powers to throw out cases before they are put to juries due to a lack of evidence;

l All police questioning of suspects should be recorded on video;

l The practice of witnesses being asked to identify people in the dock should be generally inadmissible as evidence and instead, an early pre-trial identification process should take place.

The reference group which includes human rights activists, victim support groups and a series of high-profile figures in the legal profession including judges was set up after the Criminal Justice (Scotland) Bill was passed in principle by Holyrood.

The removal of corroboration has been backed by police and prosecutors, with advocates of the policy claiming it could lead to an increased number of convictions in rape and sexual assault cases.

But opposition MSPs and many senior lawyers have raised concern it could lead to a surge in wrongful convictions.

The Post-corroboration Safeguards Review was launched in response, and will make final recommendations by April. It has identified scenarios in which it believes it would be dangerous to rely on a single piece of evidence after corroboration is scrapped.

The consultation report states: "The Reference Group are concerned to ensure that steps are taken to guard against wrongful convictions based on confessions, especially since research shows that for a variety of reasons people sometimes confess to crimes which they have not in fact committed."

It adds: "At present, no-one can be convicted on the basis of a single piece of hearsay evidence.

"With the abolition of the requirement for corroboration, convictions could be based on a single piece of hearsay evidence."

The group said the current majority verdicts "would not appear to reflect adequately the principle that guilt must be established beyond reasonable doubt", leading to risks of miscarriage of justice.

The group states that it is broadly in favour of cutting jury sizes to 12, while increasing the proportion needed to convict. It seeks views on whether a unanimous verdict should be the only one acceptable and, if not, what the size of the majority should be.

The proportions suggested by the group range from one dissenting juror to a two-thirds majority.

Brian McConnachie QC, chairman of the Faculty of Advocates' Criminal Bar Association, said the proposals showed the scale of change needed to "balance the scales" if corroboration was axed, and rejected the idea that abolition of corroboration would automatically mean a rise in sexual assault cases convictions.

He said: "They have listed a great number of things they consider would have to be done in order to find some safeguards once you remove corroboration. The fact that they have had to consider this demonstrates what folly it is to get rid of corroboration in the first place. This whole package just demonstrates the enormity of its abolition.

"On one view the removal of corroboration and the introduction of all of these safeguards could make it more easy to convict the innocent and more difficult to convict the guilty."

Thomas Ross, vice-chairman of the Faculty of Advocates' Criminal Bar Association, said: "This recognises there is a danger in removing corroboration.

"If there is no danger in it, why would you have to make special cases where you don't remove it? The idea that we are the only country that has a system to guard against human beings making mistakes in evidence is nonsense. Other countries just call it something different."