(CNN) -- George Zimmerman should only be prosecuted if, after an exhaustive investigation and an honest assessment of Florida's "stand your ground" law, special prosecutor Angela Corey concludes that there is a strong possibility of proving his guilt at trial for the killing of Trayvon Martin. No American should ever be prosecuted for any crime as a consequence of the demands of a crowd, however large or vocal. This core principle of justice should stand regardless of the facts of a case or the radioactivity of a defendant. The justice system, fragile at best, is imperiled when prosecutorial decisions are tied to politics.
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Eugene O'Donnell: Prosecutor needs to see if Zimmerman can be proven guilty
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O'Donnell: No American should ever be prosecuted for a crime because of demands of crowds
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He says prosecutors should vigorously pursue cases when justice demands it
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O'Donnell: Major challenge for prosecution would be disproving Zimmerman's story
Opinion: Without protests, justice for @placeholder can't be served