Technically, it matters. Michael Brown knew that he had done something wrong. When a LEO spoke to him about an entirely unrelated business, he was tense and ready to fight. That shouldn't be the case if one has no reason to suspect an imminent arrest.
BS. Humans go into flight-or-fight reflex.
Confront me over anything, and I'll get tense and ready to fight.
Bet on it, hero.
/johnny