There have been "serious errors" in the evidence given to a Holyrood committee over proposals to abolish corroboration, a retired high court judge has said.
Lord McCluskey has written to members of the Justice Committee stating that he is convinced they have not been given "the whole picture", particularly about the practical alternatives to removing the centuries-old need for evidence to come from at least two sources in criminal cases.
The former Solicitor General contacted the committee last week with a request to give evidence on the Criminal Justice (Scotland) Bill.
He was advised that the committee had concluded its evidence-gathering at stage one, and therefore this would not be possible.
In private correspondence sent to committee members, Lord McCluskey said he was "dismayed to receive this deeply regrettable answer".
He wrote: "I had stayed out of the matter because, having retired some years ago, I thought that others would demonstrate that the proposal to abolish the need for corroboration in all criminal cases in Scotland would have been dismissed without difficulty or abandoned in the face of the near unanimous opinion of the Judiciary.
"Additionally, when I came to read the evidence presented to the Committee, I realised that there have been serious errors in that evidence, including, I believe, evidence given by the Lord Advocate himself.
"The evidence of the Justice Secretary raised new matter, namely the idea that 'supporting evidence' would be sought. The Lord Advocate said the same. This new matter raised important issues not properly canvassed.
"I am convinced that the Committee has not been given the whole picture, particularly about the practical alternatives to the drastic step of abolishing the need for corroboration."
Lord McCluskey has already outlined his opposition to the change to the law in a newspaper article.
The controversial proposals are also opposed by other senior members of the legal profession.
But the plans, first put forward by Lord Carloway, are backed by the Justice Secretary Kenny MacAskill, the Lord Advocate Frank Mulholland and the Solicitor General Lesley Thomson.
Supporters say its removal is necessary to modernise the justice system, and could also help widen access to justice for victims, particularly in cases of rape and domestic violence where corroborating evidence can be difficult to obtain.
Those opposed fear it could have adverse consequences.
Speaking at the Justice Committee today, convenor Christine Grahame referred to Lord McCluskey's request.
She said: "In my view there was ample time for people to contribute to our evidence gathering session at stage one, and requests to give evidence were given full and proper consideration."
She added: "We all recognise that the proposals in the Bill are hugely significant. It's not possible to accommodate any further evidence at this point where we are so far down the road in considering our stage one report."
Members agreed there would be further opportunities at stage two to hear more evidence if amendments to the legislation are brought forward.
A Crown Office spokeswoman said: "The Lord Advocate set out the reasons why he believes it is right to abolish the requirement for corroboration and reassured the committee that the prosecution would set a high test for bringing cases to court which includes searching for supporting evidence to back up a complainer's account of a crime.
"These issues were fully explored by the Justice Committee during the evidence session which took place two months ago."