Trayvon was murdered in cold blood...
coldblood·ed
Pronunciation: \ˈkōl(d)-ˈblə-dəd\
Function: adjective
Date: 1595
1 a: done or acting without consideration, compunction, or clemency <coldblooded murder> b: matter-of-fact, emotionless <a coldblooded assessment>
Thus, murdered in cold blood, means that the murderer had no conscience, or emotion as he committed the act.
without emotion or feeling; dispassionate; cruel: a cold-blooded murder.
http://dictionary.reference.com/browse/cold-blooded
As for the hunted down like a dog, I'd say that speaks for itself. Tactical flashlights, 9 mm weapon with hollow-point bullets, sure sounds like he was hunted like a dog in my opinion.
~jmo~