As it prepares to give its closing arguments in the trial of George Zimmerman on Friday, the defense has a simple–but challenging–task: it must explain what the prosecution would have been required to prove, and that it has failed to do so, reminding the jury that there is more than reasonable doubt on each charge.
Murder in the second degree, the defense must explain, requires the prosecution to prove each of these elements beyond a reasonable doubt: “ The unlawful killing of a human being,  when perpetrated by any act imminently dangerous to another and  evincing a depraved mind regardless of human life.”
On #2 there is no argument. But on #3 the prosecution has provided no compelling evidence, and witness after witness–including several prosecution witnesses–testified that Zimmerman cooperated with police, was genuinely upset at Martin’s death, and acted to protect his neighbors and himself, not from depravity.
That alone should be enough to reject the charge of second-degree murder.
Furthermore, on #1 there are serious doubts, since a killing committed in self-defense is lawful if there is reasonable fear of “imminent death or great bodily harm to himself or herself or another.” The prosecution must prove Zimmerman’s fear of death or great harm was unreasonable. It has obviously failed to do so.
Zimmerman was being beaten up, quite severely. It matters little whether his injuries were actually life-threatening–though some experts said they were. It matters even less whether there were small inconsistencies in some of his statements. It does not even matter, actually, if he was following Martin.
What matters is what was going through his mind during the fight, and whether that was reasonable. If Zimmerman had been on top of Martin, if Martin had been crying for help, and if Zimmerman had been able easily to escape, that might suggest his fear was unreasonable and his resort to deadly force was unnecessary.
But the overwhelming weight of testimony indicated that Martin was on top, that Zimmerman had cried out for help, and that Zimmerman could not easily retreat. Even if the jury was not entirely convinced by that testimony it certainly creates a strong possibility that Zimmerman’s fear of peril or death was reasonable.
Because the prosecution has failed to prove beyond a reasonable doubt that Zimmerman did not act in self-defense, it has failed to prove that the killing was unlawful. So he is not guilty of second-degree murder.
What about manslaughter? The prosecution must prove each of these elements beyond a reasonable doubt: “The killing of a human being  by the act… of another,  without lawful justification according to the provisions of chapter 776 and in cases in which such killing shall not be excusable homicide or murder.”
There is no argument about #1, but #2 simply refers to the law on self-defense, as described above. Again, the prosecution has not proven beyond a reasonable doubt that Zimmerman did not “reasonably believe…that such conduct is necessary to defend himself.” Therefore Zimmerman must also be found not guilty of manslaughter.
The defense should make two additional points. One is to observe that the prosecution did not even try to walk the jury through the elements of the crime. Instead, it gave a political speech about race. In the same way, Zimmerman was the victim of a political witch-hunt from the start–as witness testimony indicates.
The other is to observe that the death of Trayvon Martin was tragic and terrible. It may even be described as unjust. But it would also be unjust to punish another man for a crime he did not commit. Perhaps we, as a society, failed Trayvon Martin. But we cannot fail George Zimmerman. You must do the right thing. Acquit.