Theresa May will vow never to allow the UK to become "looser and weaker'' in a speech ahead of a meeting in Scotland with Nicola Sturgeon.
Custody Death Family 'Seeks Truth'
Relatives of a man who died in police custody said they are unable to grieve until they know "the truth'' about the circumstances surrounding his death.
Sheku Bayoh, 31, was detained following an incident in Kirkcaldy, Fife, on May 3.
The Police Investigations and Review Commissioner (PIRC) is examining the circumstances of the father-of-two's death in custody a short time later.
Members of his family and his partner today told of their "grave concerns'' about the role of police and questioned why no officers who attended the incident have been suspended while an inquiry takes place.
The Scottish Police Federation (SPF) said police had been responding to a call of a man brandishing a knife.
Aamer Anwar, the family's solicitor, said Mr Bayoh was a "well-liked, peaceful and healthy young man'' who had no previous history of violence.
He said: "The family does not understand why the officers involved in engaging with Sheku Bayoh were not immediately suspended without prejudice after his death.
"It is a matter of wider public concern that officers remain at their desks or in contact with the public pending the outcome of the investigation into a death in custody.''
Mr Anwar claimed five different versions of events were given to Mr Bayoh's family by police officers over the course of 10 hours.
The lawyer said the family were advised officers had been called to the scene after responding to an alert following calls from members of the public.
He said reports of any officer having been stabbed were "simply untrue''.
Mr Anwar said: "For the Chief Constable to suspend the officers without prejudice is not a question of pre-judging the outcome of the investigation but ensures neutrality, integrity of the investigation, transparency as well as protecting officers involved in such incidents.''
But SPF chairman Brian Docherty said "innuendo and speculation'' while the investigation is ongoing "adds nothing other than to the pain and grief of the family''.
He said: "The Scottish Police Federation recognises that the family of Sheku Bayoh is mourning his death and that this is a painful process.
"The SPF does not wish to add to that pain by making unhelpful comments to the press. We are saddened that his legal representatives appear not to take the same approach.
"We are also saddened that his legal representatives are inferring police officers should not have the same legal protections as any other member of the public.
"A petite female police officer responding to a call of a man brandishing a knife was subject to a violent and unprovoked attack by a large male.
"The officer believed she was going to die as a result of this assault.''
Professor Peter Watson, legal adviser to the SPF, later added: "We all seek the truth and part of that truth will lie, in part, in the post-mortem and toxicology reports which will follow in due course.
"Calls for the suspension of the officers serve no purpose and do nothing but add unhelpful rhetoric in a difficult situation for all.''
Mr Anwar responded by saying the family were "deeply upset and disturbed'' at the tone of the SPF statement.
He added: "It beggars belief that police officers as of yet have not spoken to PIRC yet police federation are releasing details of what they believe to be the circumstances surrounding Mr Bayoh's death.
"The central issue in this case is one of how did Mr Bayoh die in police custody. That matter is still to be investigated.''
Mr Bayoh's partner Collette Bell, mother to his four-month-old son, described him as her "soulmate and best friend''.
"I need answers as to why he was taken from me,'' she said.
"I want to know the whole truth of the circumstances surrounding his death so that one day I can explain to my son Isaac Bayoh why he has had to grow up without his daddy.''
She was joined by Mr Bayoh's mother and two of his sisters at the media conference in Edinburgh today. They later met the Lord Advocate, who has instructed the PIRC to look at the case.
Mr Bayoh's sister Kadi Johnson talked about how he had moved to the UK from Sierra Leone when he was 11 and then to Scotland aged 17.
Mr Bayoh, who worked for British Gas, was father to four-month old Isaac and Tyler, his three-year-old son by a previous partner.
Mrs Johnson said: "At this point in time our family is heartbroken, not able to grieve; his body is still in a mortuary all alone.
"Even once we have buried my baby brother we will not be able to grieve until we know the truth.
"All we are asking for is the truth of what actually happened to my brother Sheku on morning of May 3.
"We all have grave concerns at the role of Police Scotland and are asking the Lord Advocate and the PIRC to help us get the truth.''
A PIRC spokeswoman said the independent investigation was continuing and "making good progress''. A report on its findings will be submitted to the Crown Office and Procurator Fiscal Service in due course.
After Lord Advocate Frank Mulholland met Mr Bayoh's relatives, a spokesman for the Crown Office said: "The Lord Advocate met Mr Bayoh's family this morning when he offered his condolences for their loss.
"What was discussed at the meeting will remain confidential.''
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