Indeed, local police have already released a PSA video appealing for calm as the jury considers the case. Watch it and an earlier one here.
The 36-second video features law enforcement officials, kids from the Jason Taylor Foundation and James Jones of the Miami Heat. The participants shout "raise your voice, not your hands" and "let's give violence a rest, because we can easily end up arrested." Broward County Sheriff Scott Israel said in a statement on the website that his agency has no information "about a specific event that might take place at the conclusion of the trial, but we encourage everyone to keep any protests peaceful."Interview with local police chief here. Seems like preparations launched when it became clear to many that the prosecution was fumbling the case.