No, murder is a different intent. At the end of the day what Zimmerman did was manslaughter. He didnt set out that day to kill the kid. Its one of the most misused legal terms. The only way it would be murder if the defense could prove his intent was to shoot him in cold blood or Zimmerman was in the act of committing a felony (beyond the killing, ie robbing a liquor store, this is known as felony murder). I doubt there is even a murder charge. The 911 tape proves his intent, the fact he was on watch proves his intent, the fact he followed to see what he was up to proves his intent.
Think of it this way. If you kill a guy drinking and driving, you are charged with a form of manslaughter. Your stupid act of getting behind the wheel might have been premeditated, (ie having a gun when you are a voluntary neighborhood watch) , but your intent wasnt to kill someone.
I wish the asshat could be charged with murder, but it would be overcharging him and if the manslaughter charge isnt on the table, the jury would be forced to acquit. (although the judge would most likely throw out the murder charge before the trial even began)
You've got manslaughter and second degree murder mixed up.
Like I said in my above post, it's nearly impossible to claim that you shot at a person, on purpose, and didn't intend to kill them. No, there may have been no planning to actually kill him (pre-meditiation), but the actual use of a gun and the purposeful firing of that gun at another human being goes right towards, and is pretty hard to explain away, an intent to purposefully kill. Which would make this a second-degree murder.
Just to give a real life example. Recently in Southern Ohio a woman was convicted of 2nd degree murder (in this state it's simply called murder, while 1st degree murder is called aggravated murder). She killed her husband at their home. Her husband was extremely abusive to her and their children, to the extent that she actually got them out and moved in with her family (I think it was her mother). However, after talking to her husband one day, he said that he was going to kill their children on their upcoming birthday . So, the day before their birthday, she goes to their house (fully believing the husband would follow through) and tries to talk him out of it. However, she also took with her two loaded hand-guns. Ultimately, the husband never backed down from his threat and she proceeded to shoot him and kill him.
Now, she fully believed (even if unreasonable, like Zimmerman) that her husband was a threat. So, like Zimmerman, she tried to claim self-defense (in this case defense of a third person), but in order for that claim to hold up the threat must be imminent and actual. The threat in this case wasn't imminent and so her self-defense claim failed. Furthermore, the defense asked for a lesser charge of man-slaughter, but that also was denied by the jury, because the simply act of firing a gun at another human being goes towards an intent to kill. However, the jury did buy the defense's argument that even if she did have an intent to kill, she did not plan/pre-meditate that incident and instead her initial intent was to only try to talk the husband out of killing their children. The jury DID buy that, and therefore found her not guilty of aggravated muder, but guilty of murder (2nd degree murder).
Point of that story is this, it's really hard to explain to someone that you shot at a person with no intent to actually kill them. Her man-slaughter defense rested on the notion that her husband had provoked the situation with his threat. Likewise, Zimmerman's will rest on the notion that Martin provoked the situation by confronting him/attacking him/whatever, but it will ultimately have very little to do with intent, because intent becomes obvious the moment you pull the trigger of a gun aimed at another person.
This isn't like driving drunk where you hit someone with your car. You had NO INTENT to hit that person, let alone kill them. Moreover, it's not even like an incident where you hit someone over the head with a bottle in the middle of a fight, and they end up dying from it. Your intent was to hurt them, but probably not to kill them. When you shoot someone with a gun, it almost becomes impossible to say "Didn't mean to kill, only meant to hurt." Simply doesn't work very often.