If Zimmerman is cleared, criminally, and found to have acted in self defense, then Martin's estate is barred from obtaining a civil remedy.
Is that Florida law? If so, OJ should have shopped around!
Comments here:
http://www.hlntv.com/video/2012/03/21/floridas-stand-your-ground-law-under-fire
...would seem to be saying that if SYG applies, Zimmerman has immunity, but if police don’t file charges, or if he is merely found by a jury to have acted in “self-defense,” then he MAY be sued civilly.
I don’t vouch for the accuracy of these things, just offering something for your consideration. IANAL (and stuff like this is why!)
Also, they can sue the police, and will very likely be encouraged to do so.