So this dude said it was self-defense, but in the same sentence states that it was to prevent the victim from murdering a PoC, of which there were none at the scene. This guy thought that killing this person would prevent a future murder of a PoC. It was a preemptive and justified murder in his mind on a perceived future, not reality. Self-defense means killing someone because you think they might do something later in his head.
Also can't Vice be held accountable for interviewing him and not turning him in to the authorities, press or not?