I don't know the photographer or exact year (might be 1964), but this may help getting down the road to finding out. You may remember the movie 'Mississippi Burning' about the slaying of two white civil rights workers and their black companion. I am almost positive this photo is from the trial of these policemen for the race killings with which they helped. I may be wrong, but I remember seeing this photo and reading the story behind it was directly tied to the Mississippi killings. Hope this helps...