Zimmerman was dumb enough to follow someone wearing a hoodie (often used by criminals to shield identity from surveillance cameras, but also to keep dry in the rain), walking in between buildings in the night in an area which had been hit by burglaries. Martin was dumb enough to not stay on sidewalks where he wouldn't look suspicious. Zimmerman killed the kid due to unfortunate circumstances. Especially since he was black. Put Zimmerman in jail, where a racist will kill him because of this circumstance. There... Now you have your racially motivated hate crime.