The family of a Fife man who died while being restrained by police have said they are "devastated" there will be no criminal charges against officers in connection with the case.
Sheku Bayoh's relatives said they "feel nothing but a total betrayal" over the decision not to prosecute.
Father-of-two Mr Bayoh, 31, died in Kirkcaldy in May 2015.
His family said they would seek a review of the decision and continue to fight for a public inquiry.
The Crown Office said it had conducted its investigation with "professionalism, integrity and respect".
Mr Bayoh's sister Kadijatu Johnson said: "We have left this office very disappointed and disgusted, my brother Sheku has died and yet the police get to walk free.
"The justice system has failed us as a family as well as his two boys Isaac and Tyler."
Supporters of Mr Bayoh's family held a vigil outside the Crown Office in Edinburgh as relatives met the head of Scotland's prosecution service, Lord Advocate James Wolffe QC.
Speaking after the meeting, lawyer Aamer Anwar said: "The family is devastated and feel nothing but a total betrayal by the Lord Advocate's decision not to prosecute any of the nine officers or Police Scotland.
"Sheku's family believe they have been failed by those who have a duty to protect the public and uphold the rule of law."
He said the family would "continue to fight for the truth and seek a review of the decision, albeit they believe that such a process is simply a box-ticking exercise".
Mr Anwar said they would "robustly pursue a civil action" and would "accept nothing less than a public inquiry from the Scottish government".
Mr Anwar met Justice Secretary Humza Yousaf on Wednesday afternoon.
Afterwards Mr Yousaf said: "We are not ruling out the possibility of a public inquiry. That definitely remains an option, but it is a decision that we can take only once the process around criminal proceedings has been fully exhausted.
"Once this process has concluded I have committed that I will update the family and Parliament on any next steps.
"Today was about meeting and listening to the Bayoh family and I will give full consideration to their concerns and wishes."
A Crown Office spokesman said it had been "a complex investigation", and acknowledged it had been a "difficult time" for Mr Bayoh's family and all those involved.
"The crown has conducted this investigation with professionalism, integrity and respect," he added.
"It is committed to ensuring that the facts and circumstances surrounding the death of Sheku Bayoh are fully aired in an appropriate legal forum and, to that end, it has discussed possible next steps with a small number of colleagues in the justice system.
"In order to protect any potential proceedings and to preserve the rights of the family, the Crown will not comment further at this stage."
Deputy Chief Constable Fiona Taylor, of Police Scotland, said: "Our thoughts remain with Sheku Bayoh's family and friends following his death three years ago, and we continue to offer support to anyone affected by this tragic incident.
"Police Scotland has been committed to co-operating with the Pirc [Police Investigations and Review Commissioner] and the Crown Office throughout this process, and while this continues we cannot comment further."
Mr Bayoh, a trainee gas engineer originally from Sierra Leone, died after being restrained by up to six uniformed officers in a street near his home in the Fife town on 3 May 2015.
Police had received reports of a man behaving erratically and brandishing a knife in the street.
His family's lawyer said he was not carrying a weapon when he was stopped, although the BBC understands a knife was later found nearby.
The incident was sent to the Police Investigations Review Commissioner which provided its report to the Lord Advocate 16 months after Mr Bayoh's death.
The family has been waiting for more than two years since then to discover whether prosecutors would bring charges against police officers as a result.
Mr Anwar said he wanted to know why officers used batons, CS spray, leg restraints and handcuffs to subdue him.
The family are already suing Police Scotland in a civil action on the grounds that Mr Bayoh's death could have been avoided.
How did Sheku Bayoh die?
Police received a call on the morning of Sunday 3 May 2015 about a man behaving erratically and brandishing a knife in Kirkcaldy.
Tests later revealed that Mr Bayoh had taken the drug MDMA (ecstasy) and traces of another drug A-PVP (sometimes called Flakka).
This drug has been linked to erratic behaviour.
Exactly what happened has not been made public but a BBC documentary earlier this year pieced together the events.
CCTV evidence seen by the family, but not made public, shows Mr Bayoh approaching the police at about 07:20.
The BBC understands the pictures show that he did not have a knife.
At least two officers said they believed they could be facing a terrorist incident.
At least four, and up to six, officers, were immediately involved in the encounter.
CS spray and police batons were used and within about 30 seconds, Mr Bayoh was brought to the ground, face down. Handcuffs and leg restraints were applied.
Eyewitness reports suggested that officers were kneeling and lying on Mr Bayoh in order to restrain him.
Less than five minutes after the encounter began, Mr Bayoh was noticed to be unconscious and one officer radioed for an ambulance.
A further five minutes later, the ambulance still had not arrived, and an officer reported to base that Mr Bayoh was no longer breathing.
CPR was attempted by the officers, but Mr Bayoh arrived by ambulance at the town's Victoria Hospital, where his sister works, unresponsive. He was pronounced dead at 09:04.
A post-mortem examination revealed a series of injuries over his body, face and head, including a deep gash across his forehead.
Tiny blood spots, or petechial haemorrhages were discovered in his eyes - a sign of potential asphyxia.
The post-mortem examination declared he had died after taking the drug MDMA, while being restrained.
But the family claim his death was caused by positional asphyxia - effectively being suffocated as a result of the position his body was in.
Positional asphyxia is a common cause of death in police custody where restraint is involved.
Mr Anwar told the BBC: "We've always said that if Sheku Bayoh broke the law then police had a right to act. But any force they used had to be reasonable and it had to be proportionate.
"The question for the family arises, 'If the police had not attended, would Sheku have been alive?', and I believe yes."