In Florida, as in most states, a person claiming self-defense must show that he (1) reasonably believed that such force was (2) necessary to protect himself against (3) the imminent and (4) unlawful use of force by another.
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prosecutors have a more difficult case. Now, they must prove beyond a reasonable doubt that Mr. Zimmerman did not reasonably fear for his life. The police report contains some evidence to back Mr. Zimmerman's self-defense claim. Mr. Zimmerman reportedly sustained a broken nose, cuts to the back of his head, and had grass stains on the back of his shirt. These facts could provide reasonable doubt on the self-defense question if jurors thought that Martin may have had Mr. Zimmerman pinned to the ground and was beating him. This inquiry is much more fact-intensive than relying on Mr. Zimmerman's ability to leave the scene.
Nevertheless, even with Florida's Stand Your Ground law, Mr. Zimmerman will have difficulty asserting a successful self-defense claim. Stand Your Ground laws do not affect most basic requirements of pleading self-defense. Individuals using lethal force in self-defense must reasonably believe that they are in imminent danger of death or serious bodily injury—in other words, an average person, given the facts as Mr. Zimmerman knew them, would have reached the same inferences about the danger Martin posed and the necessity of using deadly force to avoid it. Mr. Zimmerman's mere honest beliefs will not suffice.
Nor does the Stand Your Ground law permit individuals to use disproportionate force in self-defense. Mr. Zimmerman must demonstrate that he reasonably feared that Martin was going to kill him, cause great bodily injury (e.g., permanent disfigurement), or commit a forcible felony. A few cuts and a broken nose may not rise to this level. And Mr. Zimmerman will have to show that he was not the initial aggressor