The B.C. Civil Liberties Association is alleging RCMP in Prince George, B.C., told witnesses to delete video footage of the arrest of a man who later died in police custody.
The organization is also questioning whether "racial bias" played a role in the incident.
CBC has not corroborated any of the allegations raised by the B.C. Civil Liberties Association.
Dale Culver, 35, was arrested in Prince George in July 2017. Family members say he was a member of the Wet'suwet'en and Gitxsan First Nations.
According to police reports, he complained of shortness of breath and was taken to hospital, where he was pronounced dead.