Legal proceedings are to be launched against Police Scotland after a couple died when their car went off the motorway more than five years ago.
The Crown Office is understood to be taking formal proceedings against the police force.
It comes after the deaths of John Yuill, 28, and his partner Lamara Bell, 25, whose car left the M9 near Stirling in July 2015.
Despite a call being made to police, it took them three days to respond. When officers finally arrived at the scene, Mr Yuill was dead and Ms Bell died later in hospital.
Lord Advocate James Wolffe QC is understood to have notified chief constable Iain Livingstone – who was not in charge of Police Scotland at the time – that legal proceedings against the force have commenced.
A spokeswoman for the Crown Office and Procurator Fiscal Service said: “The case team and staff from our Victim Information and Advice service have communicated with family members and their legal representatives throughout, and will continue to keep them informed of any significant developments in relation to the investigation.
“In order to protect any potential proceedings, the Crown will not comment further at this stage.”
Mr Livingstone said: “Lamara Bell and John Yuill’s deaths were a tragedy and my thoughts and condolences are with their families and loved ones.
“Police Scotland has fully assisted the Crown Office throughout their inquiries and will continue to engage in due process.”
In a statement released by solicitors Digby Brown, Ms Bell’s family said: “We will not comment on any new or ongoing proceedings until they have all concluded.”