The Chair of the Sheku Bayoh Inquiry has condemned racist abuse aimed towards both the 31-year-old Kirkcaldy man's relatives and the family's solicitor.
Lord Bracadale says such abuse causes "pain, distress and harm".
Today is the start of the second phase of the inquiry examining the circumstances of Mr Bayoh's death, taking place at Capital House in Edinburgh's Festival Square.
The Chair of the inquiry said: "It has come to my attention that core participants in this inquiry have been subject to abuse on social media or in writing.
"I abhor such abuse, whatever its source and against whomever it is directed.
"Recently it has been reported to me that the family of Sheku Bayoh and their solicitor have been subjected to racist abuse.
"I am sure that everyone associated with this Inquiry will agree with me that such behaviour is despicable and entirely unacceptable.
"In some instances it may amount to hate crime.
"In every instance it causes the recipients and members of their family, some of whom may be quite young, pain, distress and harm.
"The families of Sheku Bayoh remain at the heart of this inquiry.
"The inquiry strongly condemns such treatment of them and calls for it to cease."