It's probably good police work to withhold physical evidence at least until all the witnesses can be interviewed.
If, for example, Zimmerman's account conflicts with statements he made in the 911 call, that could indicate an attempt to deceive.
If Zimmerman made any statements to police after the shooting and without legal representation, then it might confirm some peoples' suspicion that he is a fool.
Neither Zimmerman nor Martin had justification to assault the other. My understanding of "assault" is that no contact is necessary, only the justified fear of attack.
It seems reasonable to me that Martin may have been assaulted by Zimmerman's behavior in following him. This might justify Martin defending himself, but Martin's justification for taking action against Zimmerman ends if Zimmerman retreats sufficiently. At some point during a retreat by Zimmerman, Martin's actions can become an assault against Zimmerman.
The very words "Stand Your Ground" reflect the reality that one is not justified in continuing response to an attack after the attacker has withdrawn. You can stand your ground, but you can't gain ground or take the other guy's ground.
It seems to me that the challenge for a prosecutor will be to prove that Zimmerman did assault Martin and that following that assault, Zimmerman did not withdraw effectively enough to eliminate Martin's right to defend himself.
It's probably good police work to withhold physical evidence at least until all the witnesses can be interviewed.
I agree they rarely release all info until the conclusion of the case, no sense in corrupting the case.
It seems to me that the challenge for a prosecutor will be to prove that Zimmerman did assault Martin and that following that assault, Zimmerman did not withdraw effectively enough to eliminate Martin's right to defend himself.
Yes it will be a tough case, which may be why no charges were brought originally in the case.