Former Scottish Justice Secretary Kenny MacAskill has said he believes a probe into the custody death of Sheku Bayoh will show no criminality by the officers involved but that it was a tragic accident.

Mr MacAskill called for a speedy conclusion to the investigation into the death of Mr Bayoh in May and said while be believed no crime was committed "doubtless lessons can be learned and procedures adapted".

The SNP MSP added: "However, if it is of criminality that (then) I will be first to welcome it as a sign of the rigorous procedures that apply to ensure the service is not above the law.

"As it is the sooner the investigations are concluded and either a Fatal Accident Inquiry or prosecution follow the better."

Father-of-two Mr Bayoh, 31, died in custody after an alleged incident in as yet unexplained circumstances claimed to involve up to nine officers in Kirkcaldy, Fife.

A female officer was injured in the incident which began at around 7am.

It came after reports of a man carrying a knife and although it is claimed he had no knife sat the time of the arrest, in the street and is understood a blade was recovered a few yards from the scene.

The Herald: Former Just Secretary Kenny MacAskillFormer Just Secretary Kenny MacAskill

Mr MacAskill, previously a senior partner in a law firm before his 1999 election, said he believed the Scottish Government had "gone to ground" rather than move to show there was no cover-up while alleged aspects of the case were reported in the media and a claims made against officers involved.

The watchdog the Police Investigations and Review Commissioner have also been in the "shadows rather than the forefront".

Mr MacAskill said: "Police Scotland and the Lord Advocate have sought to stem the tide of criticism by narrating that investigations are ongoing and that comment is both unhelpful and inappropriate.

"However, others could and should be speaking out, not in favour of Police Scotland or the individual police officers but, in defence of the system and due process.

"That would help to counter balance the constant criticism and show the public that no cover ups can or will be allowed to arise.

"The Scottish Government established and enshrined the structures and the laws that exist for enhanced scrutiny.

"They seem, though, to have gone to ground, rather than speaking out."

Writing in an article in the Police Professional, he continued: "The Pirc, has also been in the shadows rather than at the forefront.

"It’s a relatively new post and this offers an opportunity to state who you are and what you do; to emphasise your independence and powers of investigations; and finally to state that you are in command and on the case.

He said: "When is a case neither sub-judice nor does the presumption of innocence apply?

"Well it seems in Scotland that it’s when it relates to the police service or involves a police officer.

"The usual rules of tempering comment and refraining from speculation seem to have been abrogated in a recent case."

Mr MacAskill. who is to stand down next year, added: "The police have additional powers to the ordinary citizen and as a consequence require additional supervision.

"They cannot be above the law and as in many aspects they are the law, additional rules and resources are required.

"The service and officers would expect no less.

"However, both are also entitled to the same presumptions and protections that apply to others."

Mr Bayoh's family have been campaigning for more information about the alleged events to be released including CCTV of his last moments.

The Herald: Sheku Bayoh family take protest to Holyrood and Westminster

Aamer Anwar, the Bayoh family lawyer, accused Mr MacAskill of "adding fuel to fire".

He said: "Mr MacAskill claims he will refrain from commenting but then proceeds to do exactly that and predict the outcome of the investigation."

Peter Watson, who represents the Scottish Police Federation, said: “As the lawyer representing the police officers involved, I welcome these comments from the former Justice Secretary and I agree the sooner we get to whatever judicial proceedings are to follow the better.

"This will most likely be a Fatal Accident Inquiry. This will establish the facts and do so on evidence tested in court."

A Scottish Government spokeswoman said: “This government has worked hard to strengthen legislation around scrutiny in policing and, by establishing the independent Pirc, we have ensured there is a totally robust body investigating serious incidents involving the police in Scotland.

“An independent Pirc investigation into the circumstance of Mr Bayoh’s death is already underway under the direction of the Lord Advocate and it is important to allow them to undertake their investigation and report to him.

“That process should be allowed to conclude properly without prejudging the findings.”

Kate Frame, the Police Investigations and Review Commissioner, said: “The public can be reassured that I and my team will continue to provide robust and independent investigation into incidents involving the police.

“To that end, whether it is the Sheku Bayoh case or any other, I will ensure that I do everything within my power to reveal the facts of the matter and get to the truth.”