The main concern here is to determine the facts that are in evidence, and the conclusions drawn from those facts, which translate into using the proper terms to determine guilt ot innocence. At this point, what we do know is a homicide has been committed. What is in dispute is whether or not Martin was murdered.
Pretending that words don't mean anything is the refuge of one who does not care about the facts, or wants to bend them to a predrawn conclusion.
Fine, you concern yourself with the semantic difference between murder and homicide...it is what’s important after all.