(CNN) -- The streets of Ferguson finally look like a tranquil Missouri town again. The protests have calmed. Children can safely go back to school. And after Michael Brown was laid to rest, residents are honoring his family's wish for peace. But now a different kind of strife looms: the legal battle over whether Ferguson police Officer Darren Wilson was justified in shooting and killing the unarmed teenager. Here's what to expect as the case moves forward: A grand jury will weigh the case Twelve members of a local grand jury will decide whether to bring charges against Wilson. The grand jury started hearing testimony last week, but it could take two months before jurors reach a decision.
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A grand jury is considering whether to bring charges against Officer Darren Wilson
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"It's very tough to convict an officer," a retired chief deputy U.S. marshal says
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The officer will have to "explain a reason for each of those six shots," a legal analyst says
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A federal civil rights investigation is also underway
Proving a civil rights violation in this case requires proving that @placeholder exhibited "racial hostility," CNN senior legal analyst Jeffrey Toobin said.