A key member of the Scottish government's child abuse inquiry has resigned, saying it is "doomed" by government interference.
Psychology professor Michael Lamb said there had been "repeated threats" to the independence of the Scottish Child Abuse Inquiry.
The major review is scheduled to last four years, but has been criticised by survivors of abuse.
The Scottish government said it "entirely rejects" Mr Lamb's comments.
The inquiry, which concerns historical allegations of child abuse in Scotland, will examine the extent of abuse of children in care, and identify any systemic failures.
It launched a formal call for evidence in March, but has already heard from some seriously ill or very elderly survivors.
Mr Lamb - one of three members of the panel, alongside chairwoman Susan O'Brien QC and Glenn Houston - said the project had "noble and worthy goals", but that it was ultimately "doomed".
In a letter to Education Secretary John Swinney, he said: "It has become increasingly clear over the last nine months that the panel cannot act independently and that the Scottish government intends to continue interfering in ways large and small, directly and indirectly.
"Continuing interference threatens to prevent the inquiry from investigating thoroughly and taking robust evidence of the highest quality.
"Repeated threats to the inquiry's independence have undermined the panel's freedom and have doomed the inquiry before the first witness has been heard.
"The Scottish government has delayed or prevented the appointment of crucial members of staff for prolonged periods of time while its officials have questioned the decisions made by the supposedly independent inquiry."
A spokesperson for the Scottish government said: "We entirely reject Prof Lamb's comments about the Scottish government.
"The Scottish government has a clear obligation to fulfil its responsibilities within the requirements of The Inquiries Act 2005 and other relevant legislation. Our primary focus remains on supporting the successful operation of the independent statutory inquiry.
"Ministers are grateful to Prof Lamb for his work."
The government spokesperson added: "The deputy first minister has also written to survivors and their representatives about Prof Lamb's departure and assured them that his primary objective is to ensure that this does not impact on the progress that the independent inquiry has been making."
Survivors and their representatives are due to attend a ministerial meeting to discuss the progress of the inquiry and support for victims.
Angela Constance, who established the inquiry in 2015, said the inquiry would "aim to shine a light in the dark corners of the past, to shape how we respond in the present and guide how we go forward in the future."
Ms Constance was forced to defend the inquiry's remit after campaigners claimed institutions such as the Catholic Church and Boy Scouts could be "let off the hook" by its terms of reference.