Like the George Floyd witnesses, he saw police kill a man. Now, he's part of the system, demanding change

Watching eyewitnesses in Derek Chauvin's trial express their grief, anger, fear and helplessness at seeing George Floyd beg for his life, Feidin Santana had been there before.

The 29-year-old, who recorded the fatal police shooting of Walter Scott in North Charleston, South Carolina, six years ago, had to testify himself amid threats, bigotry and bogus allegations -- all for the seemingly noble act of documenting police violence. Once on the witness stand, his character and recollections came under fire. Most familiar to Santana was last week's testimony from Donald Williams II, a mixed martial artist who implored Chauvin to take his knee off Floyd's neck, Santana told CNN. Defense attorneys tried to discredit Williams, pegging him as part of an angry mob that distracted Chauvin.