If you read the article they claim there were other images of white and Asian people too, but that the person only took a photo of the ones with a black man.
Is there a reason they have to have a photo of a real person? Is it to desensitize them to the idea of shooting someone? Just weird...
Using the term "chief" to refer to someone is not new. My uncle used to call my dad that probably 30 years ago when they worked together.